Dermatopharmacology Flashcards
1- What is the most important laboratory test you should check before starting a patient on treatment with Ixekizumab?
A. CBC with differential
B. Comprehensive metabolic panel
C. Hepatitis panel
D. Quantiferon-TB Gold
E. Fecal occult blood
Correct choice: D. Quantiferon-TB Gold
Explanation: Dermatologists should check patients for tuberculosis (TB) before they begin treatment with Ixekizumab. Healthcare providers should treat patients for tuberculosis before beginning treatment if they have a past history of TB or have TB. All providers should watch patients closely for signs and symptoms of TB during and after treatment.
2- Which of the following drugs is most likely to cause systemic lupus erythematosus with positive anti-double-stranded DNA antibodies?
A. Adalimumab
B. Hydralazine
C. Minocycline
D. Terbinafine
E. Isoniazid
Correct choice: A. Adalimumab
Explanation: Tumor necrosis factor (TNF) inhibitors, including adalimumab, have been reported to induce anti-double-stranded DNA (dsDNA)-positive systemic lupus erythematosus (SLE).
This question assesses the examinee’s knowledge of drug-induced lupus antibody profiles and inciting agents. Of the answer choices, adalimumab (choice 1) is most strongly associated with drug-induced SLE with positive anti-dsDNA antibodies. Hydralazine (choice 2) and isoniazid (choice 5) cause drug-induced SLE with positive anti-histone antibodies. Minocycline is associated with SLE featuring anti-neutrophil cytoplasmic antibody (ANCA) positivity. Terbinafine (choice 4) is associated with drug-induced subacute cutaneous LE, rather than SLE.
3- Which of the following is a potential side effect of treatment with tofacitinib?
A. Elevated transaminases
B. Leukocytosis
C. Decreased triglycerides
D. Erythrocytosis
E. Thrombocytosis
Correct choice: A. Elevated transaminases
Explanation: Tofacitinib is a JAK1/3 inhibitor used to treat several inflammtory skin conditions. Side effects include: cytopenias, elevated transaminases, and elevated triglycerides. Recently, there has been a concern that thromboembolic events may occur as well, although the data is still unclear. Cytopenias, rather than cell count increases, may occur with tofacitinib therapy. Additionally, increased (not decreased) triglycerides may occur.
4- Which of the following is NOT a potential side effect of hydroxychloroquine?
A. Retinopathy
B. Yellow discoloration of the skin
C. Hemolysis
D. Alopecia
E. Bleaching of hair roots
Correct choice: B. Yellow discoloration of the skin
Explanation: Hydroxychloroquine may produce blue-gray pigmentation of the skin, nails, and mucosae. Quinacrine may produce mucocutaneous and nail yellow pigmentation. The remaining listed answer choices may result from hydroxychloroquine administration.
- A- patient has recalcitrant Sweet’s syndrome. Hydroxyurea is initiated. Hydroxyurea works by inhibiting which enzyme?
A. Ribonucleotide reductase
B. DNA gyrase
C. Dihydrofolate reductase
D. Inosine monophosphate dehydrogenase
E. Thymidine kinase
Correct choice: A. Ribonucleotide reductase
Explanation: Hydroxyurea works as a cytotoxic agent targeting the S-phase that inhibits ribonucleotide reductase, an enzyme responsible for converting ribonucleotides to deoxyribonucleotides in DNA synthesis. Anemia, hepatitis, and renal toxicity are associated adverse effects. Fluoroquinolone inhibit DNA gyrase. Methotrexate inhibits dihydrofolate reductase. Mycophenolate mofetil inhibits inosine monophosphate dehydrogenase. Acyclovir utitilizes thymidine kinase to interrupt viral replication.
6- Which of the following is a cause of immunologic urticaria?
A. Polymyxin B
B. Amoxicillin
C. Ibuprofen
D. Opiates
E. Tartrazine
Correct choice: B. Amoxicillin
Explanation: Amoxicillin is in the penicillin family of antibiotics and is an immunologic cause of urticaria. Immunologic urticaria is most commonly caused by exposure to this family and other beta-lactam antibiotics. Patients who have a reaction to penicillins have an increased risk of cross- reacting to cephalosporins, mostly the earlier generations. The third-generation cephalosporins are less likely to cause reactions in a penicillin-allergic patient. The other listed options are causes of non-immunologic urticaria .They alter prostaglandin metabolism which increases degranulation of mast cells.
7- The most common laboratory abnormality in patients treated with isotretinoin is:
A. Decreased white blood cell count
B. Increased cholesterol
C. Elevated liver enzymes
D. Hypertriglyceridemia
E. Elevated CPK
Correct choice: D. Hypertriglyceridemia
Explanation: The most common laboratory abnormality seen in patients taking isotretinoin is increased triglycerides, followed by elevation of ALT and AST. While the other lab findings can be seen in patients on isotretinoin, they do not occur as commonly as hypertriglyceridemia.
8- Which of the following statements regarding antifungal medications is correct?
A. Griseofulvin is safe for patients with variegate porphyria
B. Ketoconazole has been associated with gynecomastia
C. Griseofulvin is a cytochrome P450 3A4 inhibitor
D. Terbinafine is fungistatic
E. Ketoconazole is fungicidal
Correct choice: B. Ketoconazole has been associated with gynecomastia
Explanation: Medications that can precipitate acute attacks in variegate porphyria include barbiturates, estrogen, griseofulvin, sulfonamides and ethanol. Ketoconazole can produce impotence and gynecomastia by interfering with androgen synthesis. Ketoconazole inhibits cytochrome (CYP) P450 and most concerning, can rarely cause fulminant hepatitis. Griseofulvin induces CYP P450, not inhibits it. Terbinafine is fungicidal along with amphotericin B. Ketoconazole is fungistatic.
A- 56 year old male presents to discuss the discoloration of his teeth he first noticed decades ago. He is advised on improving his dental hygiene and given a referral to a cosmetic dentist. What is the most likely cause of his tooth discoloration?
A. Penicillin as a child for rheumatic fever
B. Tetracycline as a child for recurrent ear and throat infections with evidence of prior veneers
C. Poor hygiene alone
D. Clindamycin as a child for deep soft tissue infection
E. Calcium deprivation as a child
Correct choice: B. Tetracycline as a child for recurrent ear and throat infections with evidence of prior veneers
Explanation: The patient received tetracycline as a child for recurrent ear and throat infections leading to staining of his teeth. He attempted prior cosmetic covering with veneers, the evidence of which you can see in the photograph. The patient should be instructed on careful hygiene and referred to a cosmetic dentist after discussion of the likely etiology. Penicillin and clindamycin do not cause staining of teeth. Poor hygiene alone does not account for the blue slate discoloration of his teeth, nor would it account for the evidence of the prior veneers. Calcium deprivation as a child would not lead to blue slate discoloration of the teeth.
10-A patient presents with nail findings seen here. Biopsy demonstrates fungus. The patient recently saw an ad for a medication (topical efinaconazole). What is the mechanism of action?
A. Antifungal via inhibiting fungal lanosterol 14-alpha-demethylase
B. Inhibits squalene epoxidase
C. Inhibits DNA gyrase
D. Inhibits epithelial sodium channels
E. Binds ergosterol and forms pores in the membrane producing potassium leakage
Correct choice: A. Antifungal via inhibiting fungal lanosterol 14-alpha-demethylase Explanation: Efinaconazole inhibits lanosterol 14-alpha-demethylase.
11- Which of the following is known to increase methotrexate levels?
A. Ondansetron
B. Ampicillin with clavulanate
C. Barbituates
D. NSAIDs
E. Acetaminophen
Correct choice: D. NSAIDs
Explanation: Tetracyclines, phenytoin, phenothiazines, chloramphenicol, NSAIDs, salicylates, and sulfonamides, among other drugs, can all increase methotrexate levels. The other options are not known to increase MTX levels.
12- Which of the following receptors, in general, is the main mediator of retinoid effects on human keratinocytes?
A. RAR-alpha
B. RAR-beta
C. RAR-gamma
D. RXR-alpha
E. RXR-beta
Correct choice: C. RAR-gamma
Explanation: Retinoids exert their effects through a variety of binding proteins including cellular retinol binding protein (CRBP), retinol-binding proteins (RBP), cellular retinoic acid-binding protein (CRABP), and nuclear receptors i.e. retinoic acid receptor (RAR) and retinoid X receptor (RXR). RAR-gamma is the most ubiquitous RAR in human skin, and is generally the main mediator of retinoid activity in the skin. The other receptors listed are not generally the main mediators of retinoid effects on keratinocytes. It should be noted that certain retinoid medications do not act on the RAR-gamma receptor (the classic example being Bexarotene, which is an RXR- specific retinoid).
13- Which of the following dietary supplements may inhibit platelet function?
A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin E
E. Vitamin K
Correct choice: D. Vitamin E
Explanation: Supplemental vitamin E can inhibit platelet function and predispose to hemorrhagic stroke. It can be particularly hazardous in patients with beta-thalassaemia mutations.
14- Which of the following medications is most likely to produce visual disturbances as a side effect?
A. Fluconazole
B. Itraconazole
C. Ketoconazole
D. Posaconazole
E. Voriconazole
Correct choice: E. Voriconazole
Explanation: Voriconazole is a second-generation azole widely used for the prevention and treatment of fungal infection in leukemia patients. Voriconazole is considered the primary antifungal agent for invasive aspergillosis. It has been reported rarely to produce visual disturbances and visual/auditory hallucinations.
15- Which of the following medications causes painful keratotic papules?
A. methotrexate
B. hydroxyurea
C. sorafenib
D. capecitabine
E. taxanes
Correct choice: C. sorafenib
Explanation: Sorafenib. Multi-kinase inhibitors ie. sorafenib, sunitnib, VEGF inhibitors have been shown to cause hand-foot skin reaction (HFSR), which presents with acral erythema and prominent hyperkeratotic plaques on areas of friction. Taxanes cause atypical hand-foot syndrome (HFS), also known as palmoplantar erythrodysesthesia or acral erythema, which presents with symmetric erythema and edema on palms and soles. Capecitabine is an oral pro-drug of 5-fluorouracil and can increases risk of HFS. The other medications listed do not cause HFSR.
16- Which of the following drugs is bactericidal?
A. Clindamycin
B. Tetracycline
C. Trimethoprim
D. Penicillin
E. Chloramphenicol
Correct choice: D. Penicillin
Explanation: Other bactericidal drugs include bacitracin, monobactams, quinolones, vancomycin, and polymyxin B. Clindamycin, tetracycline, trimethoprim, and chloramphenicol are bacteriostatic.
17- Acneiform eruptions have been associated with which of the following vitamins?
A. Vitamin C
B. Vitamin E
C. Vitamin A
D. Biotin
E. Vitamin B12
Correct choice: E. Vitamin B12
Explanation: Vitamin B12 has been reported to cause acneiform eruptions. The other listed vitamins are not associated with acneiform eruptions.
- A- 12-year-old girl with autoimmune hepatitis on oral prednisone presents with a monomorphic papular eruption on the face for 3 weeks. What is the most likely diagnosis?
A. Granuloma faciale
B. Acne vulgaris
C. Keratosis pilaris
D. Steroid-induced acne
E. Lupus disseminatus miliaris faciei
Correct choice: D. Steroid-induced acne
Explanation: Oral corticosteroid use commonly causes a specific type of acne that presents as 1-2mm monomorphic papules on the face (as well as chest and back). Granuloma faciale typically presents as a smooth violaceous to red-brown plaque on the face. Acne vulgaris is more likely to display polymorphic lesions, including open & closed comedones, papules, and/or pustules. Keratosis pilaris can present as 1-2mm monomorphic follicular-based papules on the face (and arms/thighs), but the context of an abrupt-onset during oral prednisone makes steroid-induced acne more likely. Lastly, lupus disseminatus miliaris faciei is a rare granulomatous dermatitis affecting young adults characterized by red-to-yellow or yellow-brown papules of the central face, particularly on and around the eyelids. These lesions may appear monomorphic, but the context of an abrupt-onset during oral prednisone makes steroid-induced acne more likely.
19- Which of the following retinoids is the most lipophilic?
A. Etretinate
B. Acitretin
C. Tretinoin
D. Bexarotene
E. Isotretinoin
Correct choice: A. Etretinate
Explanation: Etretinate is highly lipophilic and can last several years in fatty tissues. Isotretinoin, acitretin, and bexarotene are water-soluble, with very little lipid deposition. Water-soluble retinoids are undetectable in the serum 1 month after stopping therapy. Etretinate is 50 times more lipophilic than acitretin.
20- This patient’s only medication is allopurinol for gout. How many days ago did this patient likely start taking allopurinol?
A. 1-2 days
B. 2-6 days
C. 7-21 days
D. 21-42 days
E. 42-100 days
Correct choice: C. 7-21 days
Explanation: This patient has dusky erythematous patches and mucosal erosions indicative of SJS/ TEN due to allopurinol. SJS/TEN typically onsets 7-21 days (up to 60 days for anticonvulsant- induced SJS/TEN) after starting the offending medication. The other answer choices are not the correct durations before onset of SJS/TEN.
21- Which of the following medications is a teratogen associated with aplasia cutis congenita?
A. Propranolol
B. Methimazole
C. Lithium
D. Alcohol
E. Warfarin
Correct choice: B. Methimazole
Explanation: Aplasia cutis congenita is characterized by well-demarcated erosions at birth that heal with atrophic, alopecic scars. Some cases are caused by medications, with methimazole considered a teratogen particularly associated with this condition.
22- Which of the following medications binds the interleukin-17 receptor and acts as an antagonist specifically indicated for the treatment of adults with moderate-to-severe plaque psoriasis?
A. Ixekizumab
B. Secukinumab
C. Brodalumab
D. Risankizumab
E. Guselkumab
Correct choice: C. Brodalumab
Explanation: Brodalumab targets IL- 17 receptor. Ixekuzimab and secukinumab target IL-17, not the receptor.
23- Which of the following systemic psoriasis therapies is pregnancy category C?
A. Etanercept
B. Ustekinumab
C. Methotrexate
D. Apremilast
E. Adalimumab
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Correct choice: D. Apremilast
Explanation: Apremilast is pregnancy category C: There is no clear evidence of birth defects. Avoid unless necessary. Adalimumab, etanercept, and ustekinumab are pregnancy category B: Long-term animal studies showed no harm. No human studies conducted. Avoid unless necessary. Methotrexate is pregnancy category X: Even small doses can cause birth defects in first trimester. Absolutely avoid. Reference: PMID: 30017706
24- The pigmentation shown here is most likely due to which of the following drugs?
A. Chloroquine
B. Amiodarone
C. Minocycline
D. Doxycycline
E. TMP-SMX
Correct choice: C. Minocycline
Explanation: This slide shows blue-gray discoloration of the anterior shins and is characteristic of minocycline hyperpigmentation. The remaining answer choices are not commonly associated with blue-gray discoloration of the anterior shins.
- A- 46-year-old woman presents to the emergency room with fever and widespread confluent erythematous patches studded with pustules. CMP is normal, and CBC shows only neutrophilia. Which of the following medications is the most likely cause of this patient’s eruption?
A. TMP-SMX
B. Amoxicillin
C. Lamotrigine
D. Allopurinol
E. Phenytoin
Correct choice: B. Amoxicillin
Explanation: The stem describes the classic presentation of acute generalized exanthematous pustulosis (AGEP), which is typified by the triad of fever, neutrophilia, and eruption of punctate non-follicular sterile pustules on a background of edematous erythema. It often occurs within 1-2 days of starting the offending drug, which is most often a beta-lactam antibiotic such as amoxicillin.
The remaining answer choices are more likely to produce SJS/TEN or DRESS syndrome rather than AGEP.
26- A 30-year-old male presents with fever, stinging eyes, and pain upon swallowing which are followed by erythema and erosions of the buccal, ocular and genital mucosae. He has skin lesions that initially appeared on his trunk, spreading to his neck, face, and proximal upper extremities. His skin lesions are tender and his mucosal erosions are very painful. What is the mechanism of action of intravenous immune globulin (IVIg) in toxic epidermal necrolysis?
A. Activation of complement-mediated damage
B. Increase of circulating antibodies via anti-idiotype antibodies
C. Neutralization of toxins that trigger autoantibody inhibition
D. Inhibition of Fas (CD95)-mediated keratinocyte death
E. Functional activation of Fas-Fas ligand interactions
Correct choice: D. Inhibition of Fas (CD95)-mediated keratinocyte death
Explanation: Intravenous immune globulin is useful for inflammatory disorders, including toxic epidermal necrolysis. The dosing of IVIg in toxic epidermal necrolysis is 1 g/kg/day for 3 days. The immunomodulatory effects of IVIg may be exerted through one or more of the following mechanisms: 1) functional blockade of Fc receptors; 2) inhibition of complement-mediated damage;
3) alteration of cytokine and cytokine antagonist profiles; 4) reduction of circulating antibodies via anti-idiotype antibodies; 5) neutralization of toxins that trigger autoantibody production. In toxic epidermal necrolysis, IVIg is believed to block Fas (CD95)-mediated keratinocyte death by inhibiting Fas-Fas ligand interactions.
1 – IVIg leads to inhibition of complement-mediated damage. 2 – IVIg leads to a reduction of circulating antibodies via anti-idiotype antibodies. 3 – IVIg leads to neutralization of toxins that trigger autoantibody production. 5 – IVIg leads to functional inhibition of Fas-Fas ligand interactions.
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27- Tacrolimus is a non-steroidal anti-inflammatory medication that works by inhibiting calcineurin activity through complexing with what protein?
A. FK506 binding protein
B. TGF-beta
C. NF-kappa-B
D. SRE
E. IL-23
Correct choice: A. FK506 binding protein
Explanation: Tacrolimus and pimecrolimus are non-steroidal calcineurin inhibitors that act as anti- inflammatory medications. In dermatology, they are most commonly used in topical preparations. These medications form complexes with FK506 binding protein, which inhibits calcineurin activity. A key regulatory step in the activation of T cells is the activation of calcineurin via calmodulin.
Tacrolimus does not complex with the other listed proteins.
28- Which of the following retinoids binds to the broadest range of nuclear receptors?
A. Alitretinoin
B. Tretinoin
C. Adapalene
D. Tazarotene
E. Bexarotene
Correct choice: A. Alitretinoin
Explanation: Alitretinoin is the only retinoid that binds all retinoic acid receptors (RAR) and retinoid X receptors (RXR). This question probes the examinee’s knowledge of the receptor affinities of retinoids. Alitretinoin (9-cis-RA, choice 1) is a first-generation retinoid that binds all RAR and RXR and is used in treatment of Kaposi sarcoma. Tretinoin (all-trans-RA, choice 2) is another first-generation retinoid that binds all RAR but not RXR. Adapalene (choice 3) and tazarotene (choice 4) are third-generation retinoids that preferentially bind RAR-β/γ over RAR-α, but do not bind RXR. Bexarotene (choice 5) is third generation and binds RXR rather than RAR; it is used to treat cutaneous T-cell lymphoma.
29- Patients taking methotrexate should avoid which of the following medications?
A. ketoconazole
B. folinic acid
C. acyclovir
D. rifampin
E. trimethoprim
Correct choice: E. trimethoprim
Explanation: There is an increased risk of myelosuppression when methotrexate is coadministered with drugs that inhibit folic acid metabolism ie. trimethoprim, sulfonamides, and dapsone. The other medications do not affect folic acid metabolism. Folinic acid (leukovorin) is given to treat methotrexate-induced myelosuppression.
30- Which of the following fluoroquinolones is not associated with photosensitivity/photo- onycholysis?
A. levofloxacin
B. ciprofloxacin
C. norfloxacin
D. lomefloxacin
E. enoxacin
Correct choice: A. levofloxacin
Explanation: Levofloxacin. Levofloxacin is not associated with photosensitivity/photo-onycholysis, which is a result of UVA exposure. Lomefloxacin is associated with highest risk of photosensitivity/ photo-onycholysis.The remaining answer choices are associated with photosensitivity. Lomefloxacin is associated with highest risk of photosensitivity/photo-onycholysis.
31- You prescribe doxycyline to a 22 year-old woman with acne. Your patient takes an oral contraceptive to prevent pregnancy. Your patient read in a magazine that the doxycycline may
decrease the efficacy of her contraceptive, and asks you about this. Which of the following antibiotics has been definitively shown to reduce contraceptive efficacy?
A. Tetracycline
B. Minocycline
C. Azithromycin
D. TMP-SMX
E. Rifampin
Correct choice: E. Rifampin
Explanation: Theoretically, decreased enterohepatic absorption of hormones due to altered gut flora could decrease contraceptive efficacy. However, this theory has not been borne out in studies. Only rifampin, which is a potent hepatic microenzyme inducer, has been definitively shown to reduce contraceptive efficacy.
32- Patients with psoriasis treated with cyclosporine should be monitored for:
A. Sicca symptoms
B. Hypermagnesemia
C. Alopecia
D. Acute interstitial pneumonitis
E. Hyperkalemia
Correct choice: E. Hyperkalemia
Explanation: Well-documented adverse effects and toxicities of cyclosporine include renal impairment, hypertension, elevated triglycerides, hyperkalemia, hypomagnesemia, hepatotoxicity, hypertrichosis, and long-term increased risk of malignancy.
The other answer choices listed are incorrect.
33- Which of the following statements regarding dapsone and sulfapyridine is true?
A. They exert their anti-inflammatory actions by stimulating the myeloperoxidase activity of polymorphonuclear leukocytes
B. Dapsone hypersenstivity syndrome is characterized by lymphocytosis
C. Sulfapyridine has a similar but often more severe side effect profile than dapsone
D. Concomittant administration of cimetidine has been shown to decrease the risk of methemoglobinemia
E. Dapsone hypersensitivity is characterized by low eosinophil count
Correct choice: D. Concomittant administration of cimetidine has been shown to decrease the risk of methemoglobinemia
Explanation: Cimetidine has been shown to provide some protection against methemoglobin formation. Dapsone and sulfapyridine exert their anti-inflammatory actions by inhibiting the myeloperoxidase activity and chemotactic abilities of polymorphonuclear leukocytes. Dapsone hypersenstivity syndrome is characterized by eosinophilia, as well as a severe mononucleosis-like reaction, including fever, erythroderma, hepatitis, and even death. Sulfapyridine has a similar but often less severe side effect profile.
34- All of the following are correct about topical 5-Fluorouracil, EXCEPT:
A. Interferes with the synthesis of DNA and RNA
B. Is an alternative for the treatment of actinic keratosis
C. May cause pruritus and burning at the site of application
D. Is a Toll-like receptor 7 agonist
E. Is pregnancy category X
Correct choice: D. Is a Toll-like receptor 7 agonist
Explanation: Topical 5-FU blocks the methylation reaction of deoxyuridylic acid to thymidylic acid, thus interfering with the synthesis of DNA and RNA. Normal side effects during treatment include pruritus and burning at the site of application. It is a treatment option for patients with multiple AKs within an area. It is not recommended during pregnancy.
Imiquimod is a Toll-like receptor 7 agonist and is another treatment option for actinic keratosis.
35- Which of the following statements regarding podophyllin is most correct?
A. It is derived from the ficus plant
B. It binds tubulin
C. It arrests cells in prophase
D. It is safe in pregnancy
E. It is FDA approved to treat actinic keratoses
Correct choice: B. It binds tubulin
Explanation: Podophyllin is a crude cytotoxic extract from the May apple (Mandrake) plant. It is antimitotic, arresting cells in metaphase (not prophase) by binding to the protein tubulin. It may be teratogenic and should not be used in pregnancy. It is typically used to treat warts, particularly condyloma.
36- Which systemic anti-inflammatory agent targets CD2+ activated T cells for apoptosis?
A. Etanercept
B. Infliximab
C. Efalizumab
D. Alefacept
E. None of the above
Correct choice: D. Alefacept
Explanation: Alefacept is a soluble form of LFA-3 that blocks the immunologic synapse between CD2 on the T cell and LFA-3 on the antigen presenting cell. Furthermore, alefacept targets CD2+ activated T cells for apoptosis. Etanercept and infliximab are TNF-alpha inhibitors. Efalizumab binds to the CD11a subunit of lymphocyte function-associated antigen 1 and acts as an immunosuppressant by inhibiting lymphocyte activation and cell migration out of blood vessels into tissues. Efalizumab was associated with fatal brain infections and was withdrawn from the market in 2009.
37- The steroid with the least mineralocorticoid activity is:
A. Hydrocortisone
B. Cortisone
C. Prednisone
D. Methylprednisolone
E. Prednisolone
Correct choice: D. Methylprednisolone
Explanation: Of the corticosteroids listed, the steroid with the lowest mineralocorticoid activity is methylprednisolone. Mineralocorticoids act on the kidney to decrease the rate of sodium excretion (with accompanying retention of water). Triamcinolone, dexamethasone, and betamethasone also have low mineralcorticoid activity. The other answer choices have higher mineralcorticoid activity.
38-A patient is using imiquimod for her warts. This medicine acts on which toll like receptor?
A. 2
B. 3
C. 9
D. 5
E. 7
Correct choice: E. 7
Explanation: Imiquimod acts on toll like receptor 7. It can be used in the treatment of warts, actinic keratosis, superficial basal cell carcinomas, and squamous cell carcinomas in-situ. It also up- regulates TNF alpha, IFN gamma and alpha, and IL-12.
Imiquimod does not act on the other Toll-like receptors.
39-A patient on sorafenib for renal cancer asks what side effect she is most likely to experience?
A. Hypertrichosis
B. Nevi changes
C. Q-T prolongation
D. Cystitis after the first month
E. Redness and desquamation of the palms and soles
Correct choice: E. Redness and desquamation of the palms and soles
Explanation: Redness and desquamation of the palms and soles. This chemotherapy-induced acral erythema or hand-foot reaction is common among those taking sorafenib. Sorafenib is a chemotherapy drug. Common side effects include anemia, alopecia, hand-foot synrome, pruritus, erythema, fatigue, hypertension, GI upset, thrombocytopenia. Hypertrichosis can occur secondary to cyclosporine, Q-T prolongation can be seen with pimozide used for delusions of parsitosis and excessive amounts of lidocaine. Cystitis is characteristic of cyclophosphamide.
40- Which of the following treatments for acne inhibits RNA-dependent protein synthesis by binding to the 50s ribosomal subunit?
A. Erythromycin
B. Tetracycline
C. Trimethoprim-sulfamethoxazle
D. Benzoyl peroxide
E. Azeleic acid
Correct choice: A. Erythromycin
Explanation: Macrolide antibiotics inhibit RNA-dependent protein synthesis by binding to the 50s ribosomal subunit, and include erythromycin and azithromycin. Tetracyclines inhibit RNA- dependent protein synthesis by binding to the bacterial 30s ribosomal subunit. TMP-SMX inhibits bacterial folic acid synthesis. Benzoyl peroxide is a bactericidal agent with direct oxidizing effects. Azeleic acid is a dicarboxylic acid that inhibits tyrosinase; the mechanism of action against P. acnes is not completely understood.
41- This eruption may be precipitated by which of the following medications?
A. Hydrochlorothiazide
B. Griseofulvin
C. Hydralazine
D. Minocycline
E. Hydroxyurea
Correct choice: E. Hydroxyurea
Explanation: The image depicts the heliotrope sign of dermatomyositis. Hydroxyurea is a cytotoxic chemotherapeutic agent used for myelodysplasia. The adverse cutaneous effects due to hydroxyurea include leg ulcers, hyperpigmentation of the skin and nails, a lichen planus-like eruption, lupus erythematosus, and a dermatomyositis-like eruption.
42- This antifungal medication can have a side effect of causing rare fulminant hepatitis, gynecomastia, and impotence:
A. Terbinafine
B. Itraconazole
C. Fluconazole
D. Griseofulvin
E. Ketoconazole
Correct choice: E. Ketoconazole
Explanation: Ketoconazole can cause rare fulminant hepatitis, gynecomastia, and impotence. It inhibits CYP 450 and is a triazole and a keratinophilic.
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43- Which of the following medications is a fusion protein receptor?
A. Infliximab
B. Adalimumab
C. Risankizumab
D. Apremilast
E. Etanercept
Correct choice: E. Etanercept
Explanation: Etanercept is a fusion protein TNF-receptor that that binds to TNFα and decreases its role in disorders involving excess inflammation, including autoimmune diseases such as ankylosing spondylitis, juvenile rheumatoid arthritis, psoriasis, psoriatic arthritis, rheumatoid arthritis, and, potentially, in a variety of other disorders mediated by excess TNFα. Infliximab and Adalimumab are monoclonal antibodies that bind TNF. Risankizumab is a monoclonal antibody targeting IL-23A. Apremilast is a phosphodiesterase-4 inhibitor which inhibits spontaneous production of TNF.
44- This man started allopurinol for gout 10 days ago. What is the most likely complication from this eruption?
A. Death
B. Eruptive nevi
C. Phimosis
D. Alopecia
E. Symblepharon
Correct choice: E. Symblepharon
Explanation: This man has Stevens-Johnson syndrome (SJS) secondary to allopurinol. Symblepharon is the most common complication. As such, it is essential that patients with SJS undergo formal ophthalmologic evaluation early and often. The other remaining answer choices are potential complications from SJS, but symblepharon is most common.
45- What is the location of the unbound corticosteroid receptor?
A. Cytoplasm
B. Nucleus
C. Mitochondria
D. Plasma membrane
E. Golgi apparatus
Correct choice: A. Cytoplasm
Explanation: Both androgen and corticosteroid receptors localize to the cytoplasm. Estrogen receptors are found in the nucleus. Progesterone receptors are distributed in both the nucleus and the cytoplasm. The other listed answers are not the correct loction of the corticosteroid receptor.
46- Calcipotriene-induced improvement in psoriasis is associated with increased lesional levels of which cytokine?
A. Interleukin-2
B. Interleukin-8
C. Tumor necrosis factor
D. Interleukin-10
E. Interluekin-12
Correct choice: D. Interleukin-10
Explanation: Psoriasis is generally described as a TH1 autoimmune disease where IL-12/IFN- gamma pathway is dominant. IL-10 is the prototype of TH2 and calcipotriene application results in
increased levels of IL-10, thus decreasing TH1 disease. Calcipotriene does not increase the levels of the other listed cytokines.
47- Which biologic therapy for psoriasis has a mechanism of action that is most similar to ixekizumab?
A. Secukinumab
B. Ustekinumab
C. Adalimumab
D. Apremilast
E. Brodalumab
Correct choice: A. Secukinumab
Explanation: Brodalumab binds to the interleukin-17 receptor while ixekizumab and secukinumab target IL-17. Ustekinumab targets Il12/23 and adalimumab targets TNF- alpha. Apremilast is a PDE4 inhibitor.
48- Which of the following drugs has been associated with the development of pyogenic granulomas?
A. Doxorubicin
B. Chlorambucil
C. Isosfamide
D. Capecitabine
E. Bleomycin
Correct choice: D. Capecitabine
Explanation: At present, the pathogenesis of pyogenic granulomas is unknown. Reported triggers include antecedent trauma, pregnancy and certain drugs, including acitretin, HIV protease inhibitors, EGFR inhibitors, docetaxel, capecitabine and rituximab.
A- 28-year-old man presents with annular scaly red plaques on the upper arms and shoulders. A biopsy reveals vacuolar interface dermatitis with lymphocytes and increased mucin deposition. He tells you that he several weeks ago he started hydrochlorothiazide (HCTZ) for hypertension. Which of the following antibodies is most likely present in this man?
A. Anti-histone
B. Anti-dsDNA
C. Anti-Smith
D. Anti-SSA (Ro)
E. Anti-SSB (La)
Correct choice: D. Anti-SSA (Ro)
Explanation: The stem describes the clinico-path findings of subacute cutaneous lupus erythematosus (SCLE), which can be native or drug-induced. When caused by a medication, HCTZ is an extremely common culprit. Both native and drug-induced SCLE are associated with Anti-SSA (Ro) antibodies most commonly. Anti-histone antibodies are classically present in cases of drug- induced systemic lupus erythematosus (SLE). Anti-dsDNA and Smith are typically present in native SLE. Lastly, Anti-SSB (La) antibodies may be present in both native or drug-induced SCLE, although less commonly than Anti-SSA (Ro).
50-. Approximately what percentage of patients with drug hypersensitivity syndrome will have liver function test abnormalities?
A. Less than 10%
B. 10-25%
C. 25-50%
D. 50-75%
E. 95-100%
Correct choice: D. 50-75%
Explanation: Drug hypersensitivity syndrome is characterized by fever, skin eruption and internal organ involvement. Drugs associated with drug hypersensitivity syndrome include sulfonamindes, dapsone, anticonvulsants (carbamezapine, phenobarbitol, lamotrigine), anti-retrovirals (ritonovir, nevirapine) and minocycline. In one study, over 70% of patients had abnormal liver enzymes. The other answers do not accurately present the percentage of patients with DHS to develop liver abnormalities.
51- ACE inhibitors cause angioedema via stimulation of which of the following?
A. Bradykinins
B. Histamine
C. Prostaglandins
D. Leukotrienes
E. Complement
c
Correct choice: A. Bradykinins
Explanation: Bradykinins are responsible for angiotensin converting enzyme inhibitor-induced angioedema. The remaining answer choices are not associated with ACE inhibitor-induced angioedema.
52- Which of the following immunologic drugs has been shown to increase survival of patients with stage III and stage IV melanoma?
A. Etanercept
B. Adalimumab
C. Ustekinumab
D. Ipilimumab
E. Infliximab
Correct choice: D. Ipilimumab
Explanation: A recent study in the New England Journal of Medicine reported an increase in survival of patients with stage III and stage IV melanoma with a immunologic therapy agent named ipilimumab. The survival was increased from 6 months to 10 months (P < 0.001).
All the other medicines are not used to treat melanoma; they are used to treat psoriasis, among other disease.
53- Which of the following blocks both UVA and UVB?
A. Avobenzone
B. PABA
C. Octocrylene
D. Oxybenzone
E. Meradimate
Correct choice: D. Oxybenzone
Explanation: Oxybenzone (as well as Meroxyl XL, titanium dioxide, and zinc oxide) blocks both UVA and UVB. Avobenzone and meradimate block only UVA, whereas PABA and octocrylene block only UVB.
54- The patient developed this cutaneous adverse event 2 weeks after starting a clinical trial medication. What is the mechanism of action of the culprit medication?
A. Epidermal growth factor receptor (EGFR) inhibitor
B. Tumor necrosis factor (TNF)-alpha inhibitor
C. Smoothened inhibitor
D. BRAF inhibitor
E. Programmed cell death (PD)-1 inhibitor
Correct choice: A. Epidermal growth factor receptor (EGFR) inhibitor
Explanation: Epidermal growth factor receptor (EGFR) inhibitors cause a variety of cutaneous adverse reactions including paronychia, papulopustular (acneiform) eruption, photosensitivity, skin fragility, and hair changes. TNF inhibitors may be associated with injection site reactions and paradoxical psoriasiform eruptions. Smoothened inhibitors are associated with muscle spasm, alopecia, and dysgeusia. BRAF inhibitors are associated with maculopapular eruptions, photosensitivity, seborrheic dermatitis-like eruptions, keratosis pilaris-like eruptions and squamoproliferative growths. PD-1 inhibitors are associated with maculopapular eruption, pruritus, lichenoid eruption, and vitiligo.
55- You prescribe oral erythromycin to a 35 year-old woman. Co-administration of which of the following medications could lead to potential adverse outcomes?
A. Oral contraceptives
B. Warfarin
C. Carbamazepine
D. Methylprednisolone
E. Warfarin, carbamazepine, or methylprednisolone
Correct choice: E. Warfarin, carbamazepine, or methylprednisolone
Explanation: Erythromycin inhibits the hepatic cytochrome P450 system and can increase serum levels and potential toxicities of carbamazepine, theophylline, warfarin, digoxin, and methylprednisolone.
56- 62-year old female with history of acute myeloid leukemia presents with multiple edematous, erythematous papules after starting G-CSF. What is the most likely diagnosis?
A. Sweet’s syndrome
B. Leukocytoclastic vasculitis
C. Bowel bypass dermatosis
D. Polymorphous light eruption
E. Erythema multiforme
Correct choice: A. Sweet’s syndrome
Explanation: Sweet’s syndrome, or acute febrile neutrophilic dermatoses, is often associated with AML and G-CSF. Histologically, there is marked dermal edema with a prominent infiltrate composed of neutrophils with leukocytoclasia. There is an absence of extensive vascular damage.
57- Etretinate is this many times more lipophilic than acitretin due to increased storage in adipose tissue:
A. 10x
B. 20x
C. 30x
D. 40x
E. 50x
Correct choice: E. 50x
Explanation: Etretinate is 50x more lipophilic than acitretin, with increased storage in adipose tissue. The highly lipid soluble etretinate lasts several years in the fatty tissues, and in the presence of ethanol, acitretin is re-esterified to etretinate.
58- Menopausal flushing can be effectively treated with:
A. Nadolol
B. Tryptophan
C. Clonidine
D. Danazol
E. Tamoxifen
Correct choice: C. Clonidine
Explanation: Menopausal flushing occurs at menopause or perimenstrual when estrogen levels are low. Pharmacologic menopause may be caused by drugs, including danazol, tamoxifen, clomiphene citrate, decapeptyl, leuprolide, and 4-hydroxyandrostenedione. Treatment is with oral estrogen replacement or clonidine hydrochloride 0.05mg bid.
Nadolol is an effective treatment of emotional flushing. The other options can cause flushing.
59- Inflammation of the pictured lesions may result from treatment with which of the following?
A. 5-fluorouracil
B. Bleomycin
C. Cytarabine
D. Doxorubicin
E. Dactinomycin
Correct choice: C. Cytarabine
Explanation: Cytarabine, used for the treatment of acute myelogenous leukemia, can cause a rare reaction of inflammation of existing seborrheic keratoses. The other answer choices have not been reported to produce a reaction of inflammation of existing seborrheic keratoses.
60- Which of the following adverse effects may occur with cyclosporine administration?
A. Decreased potassium
B. Hypotension
C. Hypotrichosis
D. Decreased uric acid
E. Decreased magnesium
Correct choice: E. Decreased magnesium
Explanation: Cyclosporine use is associated with decreased serum magnesium levels. Thus, magnesium levels should be monitored and magnesium supplementation given as needed for patients taking cyclosporine. Cyclosporine is associated with several potential adverse effects, including: nephrotoxicity, reversible hypertension, gingival hyperplasia, hyperlipidemia, paresthesias, hypertrichosis, and increased serum levels of potassium and uric acid.
61- This HIV-positive patient has ~15% BSA involvement. Which of the following is the best initial systemic treatment for this patient?
A. Methotrexate
B. Cyclosporine
C. Adalimumab
D. Infliximab
E. Acitretin
Correct choice: E. Acitretin
Explanation: This HIV-positive patient has psoriasis requiring systemic therapy. Of the options listed, only acitretin is non-immunosuppressive and thus should be the first systemic therapy in this case. The remaining answer choices are less ideal in this HIV-positive patient considering that they are immunosuppressive.
62- Which side effect causes most patients to discontinue vismodegib?
A. fatigue
B. diarrhea
C. muscle spasms
D. dysgeusia
E. hair loss
Correct choice: C. muscle spasms
Explanation: Muscle spasms are the most common side effect and cause the most patients to discontinue vismodegib.
63- This patient also has extensive oral erosions. He tells you his only new medication is dicloxacillin, which he is taking for impetigo. How many days prior to development of the pictured eruption did this patient most likely begin taking dicloxacillin?
A. Hours-2 days
B. 7-21 days
C. 21-56 days
D. 60-90 days
E. >180 days
Correct choice: B. 7-21 days
Explanation: Extensive oral erosions coupled with widespread epidermal detachment is highly concerning for Stevens-Johnson syndrome/Toxic epidermal necrolysis (SJS/TEN), which is a severe cutaneous adverse reaction that is almost always drug-related. The most common offending drugs include: antibiotics (especially sulfonamides and penicillins), allopurinol, anticonvulsants (often
lamotrigine, carbamazepine, or phenytoin), barbiturates, NSAIDs, and anti-retrovirals. For SJS/ TEN, the typical onset of eruption after drug ingestion is 7-21 days (although it can be up to 60 days for anticonvulsants). Hours to 2 days is typical for acute generalized exathematous pustulosis (AGEP). Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome usually occurs 21-56 days after medication exposure. Lichenoid drug eruptions and drug-induced pemphigus may occur several weeks or months after drug initiation.
64- In the 1960s, a series of drug-induced cases of a congenital disorder involving malformation of the limbs multiplied leading to various abnormalities of the limbs, ears, nose, vessels, face, and many other underdevelopments. The teratogenic drug responsbile inhibits expression of this cytokine:
A. IL-23
B. IL-10
C. TNF-alpha
D. TGF-beta
E. G-CSF
Correct choice: C. TNF-alpha
Explanation: Thalidomide inhibits TNFa expression. TNFa is the primary mediator of acute inflammation, fever, and hepatic production of acute phase reactants. Thalidomide does not regulate the other cytokines listed above.
65- The putative mechanism of action of topical macrolide immunomodulators is inhibition of:
A. Lymphokine production
B. Prostaglandin secretion
C. Antigen presentation
D. Neutrophil migration
E. Lymphocyte migration
Correct choice: A. Lymphokine production
Explanation: Tacrolimus and pimecrolimus are topical macrolide immunomodulators that inhibit lymphokine or cytokine production via binding to macrophilin. This complex inhibits calcineurin, a phosphatase involved in the activation of NF-AT. This suppresses the production of IL-2 and IFN- gamma (TH1 cytokines) as well as IL-4, 5 and 13 (TH2 cytokines). In addition, they decrease the expression of IgE receptors on Langerhans cells and reduce mast cell degranulation. Topical macrolides do not interfere with antigen production, prostaglandin secretion and neutrophil/ lymphocyte migration.
66- Which of the following drugs has not been implicated in drug-induced subacute cutaneous lupus erythematosus:
A. Terbinafine
B. Verapamil
C. Pravastatin
D. TNF-alpha inhibitors
E. Azithromycin
Correct choice: E. Azithromycin
Explanation: SCLE most commonly presents as psoriatic or annular/polycyclic erythematous scaly patches and plaques in a photo distribution. The condition is often drug induced with many traditional culprits but Azithromycin is not one. All of the other choices have been implicated in drug-induced subacute cutaneous lupus erythematosus.
67- A patient presents with onycholysis after sun exposure. Which of the following medications would be LEAST likely as a cause of this presentation?
A. Quinolones
B. Tetracyclines
C. Psoralen
D. Quinine
E. Chlorpromazine
Correct choice: E. Chlorpromazine
Explanation: Chlorpromazine is associated with blue-gray pigmentation on sun-exposed areas and is not associated with photoonycholysis. Quinolones, tetracyclines, psoralens and quinine can cause photoonycholysis.
68- A patient with metastatic melanoma was placed on trial medication .after one month of treatment ,she developed numerous hyperkeratotic papules on the face and extremeties as seen in the photo .what was most likely mechanism of the drug?
A-MEK inhibitor
B- BRAF inhibitor
C-interleuken-2
D-CTLA-4 inhibitor
E-interferon -alpha
Correct choice: B- BRAF inhibitor
Monotherapy with BRAF inhibitor have been associated with hyperkeratotic papules,verruca,keratoacanthomas , SCC in up to 30 % of patients. Combination therapy with MEK inhibitor have drastically reduced this side effect.
69- A 65 year-old female with multiple actinic keratosis on the face is under treatment with 5-FU. According to the image (erosions, crusting) and aforementioned information, you may conclude that:
A. The patient must immediately stop treatment since unexpected side effects have developed
B. She requires intravenous acyclovir treatment.
C. The patient has been compliant with 5-FU treatment and the appearance of inflammation, erythema and erosions are expected
D. The presumed diagnosis of actinic keratosis was incorrect.
E. The image is not relevant to 5-FU treatment
Correct choice: C. The patient has been compliant with 5-FU treatment and the appearance of inflammation, erythema and erosions are expected. Compliance is a key feature in treatment with 5-FU. Erythema, inflammation and erosion must develop and is considered a sign of successful treatment.
70- A patient with Hailey-Hailey disease declines systemic treatment and has failed stand-alone topical steroid treatment x 6 months. What is a reasonable next treatment to offer the patient?
A. Ethyl alcohol
B. 5-fluorouracil
C. Lidocaine
D. Silver sulfadiazine
E. Gentian violet
Correct choice: B. 5-fluorouracil
Explanation: 5-fluorouracil can be an effective treatment for benign familial pempigus or Hailey- Hailey disease, having induced remission of the disease in a subset of patients after 6 months to a year of tapered treatment.
71- A patient with plaque psoriasis and psoriatic arthritis has recalcitrant disease (~15% body surface area) despite being treated with topicals, phototherapy, and methotrexate. He is HIV+ and works in a prison. Which of the following options is the most appropriate next treatment to control his psoriasis?
A. Cyclosporine
B. Apremilast
C. Ustekinumab
D. Infliximab
E. Prednisone
Correct choice: B. Apremilast
Explanation: Apremilast should be strongly considered in this patient. He is at risk for infections due to his occupation (especially tuberculosis) and HIV+ status. Ustekinumab and infliximab may put the patient at higher risk for infection, including tuberculosis. Prednisone and cyclosporine are not good long term management options. Apremliast theoretically does not put the patient at higher risk of infection due to its mechanism (PDE4 inhibition).
72- A patient on ixekizumab injection for psoriasis reports injection site reactions after each injection that are red and bothersome, lasting about 30 minutes to one hour. What is the next most reasonable step?
A. Space the injections out by an additional 2 weeks
B. Stop ixekizumab and start infliximab
C. Pre-medicate with acetaminophen 1 g by mouth, diphenhydramine 25 mg by mouth, and allow the injection to reach room temperature prior to injection
D. Begin prednisone 5 mg by mouth the morning of each injection
E. Switch biologic to guselkumab
Correct choice: C. Pre-medicate with acetaminophen 1 g by mouth, diphenhydramine 25 mg by mouth, and allow the injection to reach room temperature prior to injection
Explanation: Premedication and allowing the medication to reach room temperature reduce injection site reactions. The remaining choices are not the next most reasonable steps for injection site reaction on ixekizumab.
73- What is the mechanism of action of tildrakizumab asmn?
A. IL-17 blockade
B. IL-23 blockade
C. PDE-4 inhibitor
D. TNF-alpha blockade
E. IL-12/23 blockade
Correct choice: B. IL-23 blockade
Explanation: Tildrakizumab-asmn is a humanized IgG1/k monoclonal antibody that selectively binds to the p19 subunit of IL-23 and inhibits its interaction with the IL-23 receptor. IL-23 is a naturally occurring cytokine that is involved in inflammatory and immune responses.
74- A 65 y/o male is referred by his oncologist for new onset yellowing of the skin. Which of the following drugs is this patient most likely on?
A. Sunitinib
B. Pembrolizumab
C. Imatinib
D. Vemurafenib
E. Cetuximab
Correct choice: A. Sunitinib
Explanation: Sunitinib is a tyrosine kinase inhibitor for VEGFR and PDGFR in GI stromal tumors, pancreatic neuroendocrine tumors, and renal cell cancers. While it is generally a well tolerated chemotherapeutic agent, it can have dermatologic side effects, such as yellowing of the skin. Vemurafenib is a BRAF inhibitor, which can cause warty keratoses and new SCC/KAs.
Pembrolizumab is a PD1 inibitor, which can cause autoimmune, vitiligo-like, and lichenoid reactions. Cetuximab is an EGFR inihibitor, which can cause an acneiform rash. Imatinib is a tyrosine kinase inhibitor, which can cause periorbital edema and hypopigmented/depigmented eruptions.
75- Other than a topical steroid, which topical medication may have particular use in non-infected Darier disease that is mildly inflamed and pruritic.
A. Clotrimazole
B. Ketoconazole
C. Diclofenac
D. Gentian violet
E. Lidocaine
Correct choice: C. Diclofenac
Explanation: Diclofenac topical may provide anti-inflammatory action for pruritic and inflamed Darier disease. The remaining choices are incorrect.
Reference: J Am Acad Dermatol. 2014 Apr;70(4):e89-e90. doi: 10.1016/j.jaad.2013.11.033. Improvement of Darier disease with diclofenac sodium 3% gel. Millán-Parrilla F1, Rodrigo-Nicolás B2, Molés-Poveda P2, Armengot-Carbó M2, Quecedo-Estébanez E2, Gimeno-Carpio E2.
76- What is the mechanism of dupilumab?
A. Monoclonal antibody to IL-4 receptor
B. Monoclonal antibody to IL-5
C. Monoclonal antibody to IL-4
D. Monoclonal antibody to CD4
E. Monoclonal antibody to IL-13
Correct choice: A. Monoclonal antibody to IL-4 receptor
Explanation: Dupilumab has been studied for atopic dermatitis and binds to the IL-4R alpha. This modulates signaling of IL-4 and IL-13. Mepolizumab is an IL-5 inhibitor. Several humanized monoclonal antibodies to IL-13, including anrukinzumab, lebrikizumab and tralokinumab, are currently under clinical evaluation.
77- What is the primary mechanism of action of oxymetazoline HCl 1% cream?
A. Destruction of cutaneous blood vessels
B. Vasoconstriction
C. Vasodilation
D. Anti-inflammatory
E. Anti-parasitic
Correct choice: B. Vasoconstriction
Explanation: Oxymetazoline HCl 1% works via vasoconstriction of cutaneous vessels in patients with rosacea. The medication is an alpha 1A adrenoceptor agonist. Vasodilation is the opposite effect we want in patients with rosacea. Pulsed dye laser aims via destruction of cutaneous vessels. Ivermectin is a topical and systemic agent that is anti-parasitic and used to treat rosacea. Several antibiotics - both by mouth and by topical application - work to reduce inflammation in the skin of patients with rosacea. https://doi.org/10.1016/j.jaad.2018.01.027.
78- A 72 year old white female with history of kidney transplant and 22 squamous cell skin cancers (SCC) presents as a new patient at your office. She has hundreds of actinic keratoses on physical exam. In addition to photoprotection and skin checks, what additional steps might prove helpful to reduce the number of SCC for this patient?
A. Decline any further non-melanoma skin cancer treatments
B. Begin pre-emptive superficial radiation therapy of lesions that appear suspicious
C. Perform 50% TCA peels on all sun exposed parts of the body
D. Discuss starting nicotinamide and acitretin with the patient
E. Stop all immune rejection medications
Correct choice: D. Discuss starting nicotinamide and acitretin with the patient
Explanation: Evidence suggests that in high risk populations with many non-melanoma skin cancers nicotinamide and acitretin may reduce the development of new non-melanoma skin cancers along with photoprotection and close surveillance. The remaining choices are either dangerous to the patient or inappopriate medical care. TCA peels can be used on certain parts of the body for patients who have failed photodynamic therapy and/or 5-fluorouracil or imiquimod but the strength is not 50% - you could use 35% TCA with Jessner’s on the face and TCA 25% on the neck, chest, arms, hands, legs, and feet with close attention to the depth of the peel on the extremities, neck, and chest.
79- A patient calls the on-call physician complaining of a metallic taste but doesn’t remember his medication list. Which of the following is the most likely culprit?
A. Terbinafine
B. Fluconazole
C. Minocycline
D. Sulfamethoxazole-trimethoprim
E. Amoxicillin-clavulanate
Correct choice: A. Terbinafine
Explanation: Terbinafine is a fungicidal medication used for onychomycosis that can cause dysgeusia, or metallic taste. The other medications listed do not cause dysgeusia.
80- Which of the following treatments likely has the best cost-benefit ratio (cost of medication compared to the likelihood of the patient having significant improvement) for a patient with psoriasis?
A. Ustekinumab
B. NB-UVB
C. Acitretin
D. Methotrexate
E. Adalimumab
Correct choice: D. Methotrexate
Explanation: Although not all costs were factored, one 2015 study found that methotrexate and cyclosporine had the most favorable monthly costs (number needed to treat to achieve PASI 75) for treatment of psoriasis. Infliximab and ustekinumab were the most expensive treatment options for psoriasis.
81- A 35 y/o male presented to his dermatologist for a suspected infection after a skin biopsy. The dermatologist prescribed a medication that blocks the ribosomal 30S subunit to treat the infection. Which of the following medications was prescribed?
A. Mupirocin
B. Levofloxacin
C. Doxycycline
D. Retapamulin
E. Amoxicillin/Clavulanate
Correct choice: C. Doxycycline
Explanation: Doxycycline is a tetracycline antibiotic which inhibits protein synthesis by binding to the 30S ribosomal subunit. It is effective against both gram-positive and gram-negative infections.
Retapamulin is incorrect as it blocks the 50S ribosomal subunit. Amoxicillin/Clavulanate blocks bacterial cell wall synthesis by binding the transpeptidase/penicillin binding proteins and is enhanced by clavulanic acid binding beta-lactamase. Mupirocin blocks t-RNA synthetase. Levofloxacin blocks DNA Gyrase/topoisomerase II.
82- A 35 y/o female with a personal history of Crohn’s disease and depression is diagnosed with psoriasis covering 15% of her body. She also has a family history of multiple sclerosis in her mother. Which of the following is the most appropriate first line treatment for this patient?
A. Brodalumab
B. Apremilast
C. Ixekizumab
D. Tildrakizumab
E. Etanercept
Correct choice: D. Tildrakizumab
Explanation: Tildrakizumab would be an ideal first-line agent in this patient given her co- morbidities (IBD, depression, and FHx of MS), but significant psoriatic burden. Tildrakizumab (Ilumya) is an human antibody directed against the p19 subunit of IL-23. IL-23 inhibitors are not contraindicated in depression, IBD, or in patients with a family history of MS. Apremilast and Brodalumab are incorrect due to the patient’s history of depression. Etanercept is incorrect because of the direct family history of multiple sclerosis, which is contraindicated in TNF-a inhibitors.
Ixekizumab and Brodalumab are incorrect due to the patient’s history of inflammatory bowel disease, which is contraindicated in IL-17 inhibitors.
83- A 35 year-old otherwise healthy man presents with moderate-to-severe plaque psoriasis, improved on cyclosporine. The patient weighs 70 kilograms and is taking a dose of 300 mg/day. His baseline creatinine was 0.8; on follow-up testing it is 1.1. All other exam and laboratory parameters are within normal limits. The patient is pleased with his treatment and asks to continue it. Which of the following is the most appropriate next step?
A. The creatinine should be rechecked in 2 weeks and then the patient reassessed.
B. You offer a decrease of the cyclosporine dose to 225 mg/day and close follow-up
C. Cyclosporine rarely has renal toxicity in young, healthy individuals; thus you must work-up other causes of the increased creatinine
D. The cyclosporine should be stopped immediately; the patient must avoid cyclosporine in the future
E. The change in creatinine is not significant, no change is needed
Correct choice: A. The creatinine should be rechecked in 2 weeks and then the patient reassessed.
Explanation: Cyclosporine is highly effective in most patients with severe chronic plaque-type psoriasis. Doses start at 2.5 to 4mg/kg/day and can go as high as 5.5mg/kg/day. Renal impairment may occur and is often reversible. If the creatinine increases 30% or greater from baseline, it should be repeated in 2 weeks to verify the increase is persistent and then the dose should be reduced by 25% and the patient followed closely.
84- Which of the following medications is most likely to induce yellow skin discoloration?
A. Sorafenib
B. Dabrafenib
C. Sunitinib
D. Vemurafenib
E. Dasatinib
Correct choice: C. Sunitinib
Explanation: Sunitinib is reported to cause yellow skin discoloration.
This question checks the examinee’s knowledge of targeted cancer therapy-related skin reactions. Although all of the answer choices have been reported to cause multiple cutaneous effects, some reactions are more closely linked to particular agents and thus more likely to be tested. Sunitinib (choice 3) is a multikinase inhibitor that can cause a characteristic yellow discoloration of the skin. Dasatinib (choice 1), another multikinase inhibitor, is associated with Sweet syndrome, panniculitis, and urticaria, among other cutaneous side effects. The BRAF inhibitors, dabrafenib (choice 2) and vemurafenib (choice 5), are well known to induce keratoacanthomas and squamous cell carcinomas, an effect ameliorated by combination with a MEK inhibitor. Sorafenib (choice 4) is another multikinase inhibitor that can also cause yellow skin discoloration, but less frequently than sunitinib.
85- A horticulturist of sphagnum moss topiaries comes in with a nodular eruption with lymphangitic spread. Treatment with oral potassium iodide is initiated. What is the most well recognized side effect of this treatment?
A. Angioedema
B. Flushing
C. Gastrointestinal distress
D. Pruritus
E. Shortness of breath
Correct choice: C. Gastrointestinal distress
Explanation: This patient has sporotrichosis. Sporotrichosis is mainly an occupational disease of farmers, gardeners, and horticulturists. Persons who handle thorny plants, sphagnum moss, or baled hay are at increased risk. Outbreaks have occurred in nursery workers who handled sphagnum
moss, rose gardeners, children playing on baled hay, and greenhouse workers who handled bayberry thorns contaminated by the fungus. Classic treatment is with oral potassium iodide for 3-4 weeks. The most recognized side effect of treatment is gastrointestinal distress. Thyroid function tests should be performed during treatment as suppression can occur.
86- Which of the following is the mechanism of ixekizumab?
A. IL-17A monoclonal antibody
B. IL-17RA monoclonal antibody
C. Inhibits phosphodiesterase-4
D. IL-12 & IL-23 antagonist
E. TNF antagonist
Correct choice: A. IL-17A monoclonal antibody
Explanation: Ixekizumab and Secukinumab are both IL-17A monoclonal antibodies. B describes Brodalumab which is an IgG2 against the IL-17 receptor; therefore it inhibits pan-IL-17, including A, A/F, E, F, and C receptors C describes apremilast which blocks PDE4, resulting in ↑ cAMP levels which inhibits production of proinflammatory cytokines. D describes ustekinumab which is an IgGκ against the p40 subunit of IL-12 & IL-23. E describes Etanercept, Adalimumab, Infliximab, Golimumab, and Certolizumab which are TNFa inhibitors.
87- What is the primary mechanism of action of risankizumab-rzaa, a medication used to treat psoriasis?
A. TNF alpha blockade
B. IL-12/23 blockade
C. IL-23 blockade
D. PDE-4 inhibitor
E. IL-17 blockade
Correct choice: C. IL-23 blockade
Explanation: Risankizumab-rzaa is a humanised immunoglobulin G1 (IgG1) mAb, which selectively binds to IL-23 cytokine and blocks its interaction with the IL-23 receptor. Naturally occurring in the human body, the IL-23 cytokine is responsible for inflammatory and immune responses. IL-17, IL-12/23, PDE-4, and TNF alpha blockade describe the mechanisms of action for other medications used in the treatment of psoriasis and other conditions.
88- Which of the following concomitant medications is recommended to decrease the development of anti-drug antibodies to be used at the same time as a biologic for the treatment of psoriasis?
A. Acitretin
B. NB-UVB
C. Methotrexate
D. Mycophenolate mofetil
E. Low dose prednisone
Correct choice: C. Methotrexate
Explanation: The correct answer is B, methotrexate. The current recommendation to possibly decrease the risk of anti-drug antibodies (if desired) in the treatment of psoriasis is the concomitant use of methotrexate. The other medications listed have not been shown to decrease anti-drug antibodies to biologics used in psoriasis.
89- What is a common side effect of dupilumab?
A. Diarrhea
B. Hyperlipidemia
C. Tremors
D. Acute renal failure
E. Conjunctivitis
Correct choice: E. Conjunctivitis
Explanation: Dupilumab does induce conjunctivities in a subset of patients using the medication, which is FDA approved to treat atopic dermatitis.
90- A patient with psoriasis with BSA 40% would like to try a biologic medication as he has failed nbUVB therapy. He is very needle phobic. Which biologic might be easiest for the patient to adhere to?
A. Etanercept
B. Ixekizumab
C. Adalimumab
D. Guselkumab
E. Ustekinumab
Correct choice: E. Ustekinumab
Explanation: Ustekinumab is an injection given every 3 months as maintenance therapy for the indication of psoriasis. The remaining choices are incorrect as they are given every week (etanercept), every two weeks (adalimumab), every month (ixekizumab), and every two months (guselkumab) as maintenance therapy - these responses do not represent the longest interval that would reduce needle phobia experience.
91- This 48-year-old man was recently diagnosed with osteomyelitis and started vancomycin and piperacillin-tazobactam 2 days ago. He is on no other medications. Today you are consulted to evaluate the pictured rash on his upper chest and neck. Which of the following is true regarding the most likely diagnosis?
A. Vancomycin is the most likely cause
B. Edema of the face and hands may be seen
C. Fever is typically absent
D. IVIG is the treatment of choice
E. Peripheral eosinophilia is characteristic
Correct choice: B. Edema of the face and hands may be seen
Explanation: This patient has acute generalized exanthematous pustulosis (AGEP). AGEP is a severe cutaneous adverse reaction that typically develops 1-3 days after starting the offending drug. In addition to the rapid appearance of widespread, sterile, non-follicular pustules, edema of the face and hands may be seen. AGEP is most often caused by beta-lactam antibiotics, making piperacillin- tazobactam a more likely culprit than vancomycin. Fever and neutrophilia (not eosinophilia) are characteristic of AGEP. Drug withdrawal and supportive care are the mainstays of treatment.
92- In a patient with mild depression on isotretinoin who experiences mild worsening of baseline depression symptoms, what add-on treatment may be effective to reduce depression symptoms?
A. Folic acid supplementation
B. High dose vitamin C (> 5,000 mg per day by mouth)
C. Calcium supplementation
D. Methotrexate by mouth
E. Vitamin D 2000 units per day by mouth
Correct choice: A. Folic acid supplementation
Explanation: Isotretinoin (ISO) is a first-generation retinoid discovered in 1952 and approved by the FDA for the treatment of nodulocystic acne in 1982. The anti-inflammatory properties of ISO have found its use in disorders other than acne. ISO can create psychiatric problems, including depression and suicidal ideation. These neuropsychiatric problems are very similar to disorders secondary to hyperhomocysteinemia (HHcy), vitamin B12, and folic acid (vitamin B9) deficiencies. Given that previous literature suggested folate supplementation improved the efficacy of traditional antidepressant medications, clinicians may wish to consider folate supplementation for patients with depression or possible depressive symptoms, such as acne patients with genetic susceptibility.
93- You want to start a patient on terbinafine for onychomycosis. Which of the following medications would be a contraindication for doing so?
A. Propranolol
B. Glipizide
C. Metformin
D. Aspirin
E. Lisinopril
Correct choice: A. Propranolol
Explanation: Terbinafine is a potent inhibitor of CYP2D6 and therefore could cause bradycardia when given with beta blockers, such as propranolol. Given this property, it can also cause oversedation when given with some SSRIs, such as doxepin. Metformin, glipizide, lisinopril, and aspirin do not have contraindications with terbinafine use.
94- This 20-year-old woman started lamotrigine 3 weeks ago. She takes no other medications, and has no comorbid conditions. Her urine b-HCG is positive. Which of the following treatments has the theoretically lowest fetal risk?
A. IVIG
B. Cyclosporine
C. Prednisone
D. Etanercept
E. Rituximab
Correct choice: D. Etanercept
Explanation: This woman has Stevens-Johnson syndrome (SJS) secondary to lamotrigine. The treatment of SJS/TEN is controversial and variable given the paucity of high-quality data. Nevertheless, publications exist that support the use of various immunomodulators, including etanercept, prednisone, IVIG, and cyclosporine. Etanercept is the only one of these options that is pregnancy category B, indicating animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women. Prednisone, IVIG, and cyclosporine are all pregnancy category C (animal studies show a fetal risk and there are no adequate human studies) and therefore carry a theoretically increased fetal risk compared to etanercept. Rituximab is not used in the treatment of SJS/TEN, and is also pregnancy category C.
95- A patient presents with a widespread papular eruption. Biopsy shows a band-like infiltrate in the superficial dermis. Which of the following medications is the most likely culprit?
A. Topical Clobetasol
B. Captopril
C. Doxycycline
D. Hydralazine
E. Penicillin
Correct choice: B. Captopril
Explanation: The stem and image describes a patient with a lichenoid drug eruption. Captopril is an ACE inhibitor which is classic cause for lichenoid drug eruptions. Other medications causing lichenoid eruptions include HCTZ, antimalarials, NSAIDS, gold, and D-penicillamine.
Doxycycline can cause fixed drug eruptions and phototoxic reactions. Topical clobetasol causes an acneiform eruption. Hydralazine causes an SLE-like rash. Penicillin is classic for morbilliform eruptions and Linear IgA dermatosis.
96- A patient with lichen planopilaris has failed intralesional steroids, topical steroids, doxycycline, and finasteride for 6 months. She is desperate for anything that might help. What is a reasonable next treatment to offer the patient?
A. Rituximab
B. Cyclophosphamide
C. Low dose naltrexone
D. Pulsed high dose intravenous steroids
E. Mycophenolate mofetil
Correct choice: C. Low dose naltrexone
Explanation: Low dose naltrexone can improve the inflammation of lichen planopilaris. The remaining choices are dangerous or inappropriate for the management of lichen planopilaris.
97- Which of the following drugs has been most commonly associated with eyelash trichomegaly?
A. Vismodegib
B. Pembrolizumab
C. Infliximab
D. Imatinib
E. Erlotinib
Correct choice: E. Erlotinib
Explanation: Erlotinib is an EGFR inhibitor known for its efficacy in the treatment of NSCLC and pancreatic cancers. It has been reported to cause eyelash trichomegaly. Imatinib, Infliximab, Vismodegib, and Pembrolizumab have not been reported to cause trichomegaly.
98- What caused this reaction?
A. Simvastatin
B. Indinavir
C. Zidovudine
D. Methotrexate
E. Ciprofloxacin
Correct choice: C. Zidovudine
Explanation: The pigmented nail streaks are a known side effect of zidovudine. Nail pigmentation can be drug induced. This includes:
-Brown or black transverse and/or longitudinal bands — which can be due to melanonychia (melanocytes stimulation) from zidovudine, psoralens (PUVA), hydroxyurea and other chemotherapy drugs
-Yellow transverse pigmentation — which can be due to tetracyclines
-Bluish grey pigmentation of the nail bed that does not move outwards— which can be due to minocycline
-Brownish discolouration of the nail bed — which can be due to antimalarial drugs (hydroxychloroquine and chloroquine) .
99- A patient with psoriasis BSA 60% is about to start brodalumab. What black box warning should you discuss with the patient prior to enrolling the patient to receive the medication?
A. Conjunctivitis
B. Acute liver failure
C. Gangrene
D. Suicidal ideation and completion
E. Acute respiratory distress syndrome
Correct choice: D. Suicidal ideation and completion
Explanation: The FDA issued a black box warning after six patients treated with brodalumab across four clinical trials committed suicide, but no causal relationship was identified. Current evidence suggests a similar safety profile for brodalumab compared to other IL-17 antagonists used to treat moderate-to-severe plaque psoriasis. The remaining choices are incorrect as they do not represent the black box warning for brodalumab.
100- A 45 y/o female with a history of a renal transplant, presents for Mohs surgery on her 25th SCC. Which of the following immunosuppressants has the lowest risk of further SCC development?
A. Mycophenolate
B. Azathioprine
C. Prednisone
D. Cyclosporine
E. Sirolimus
Correct choice: E. Sirolimus
Explanation: Sirolimus (rapamycin) is an mTOR inhibitor which causes the downregulation of the PI3K/AKT signaling pathway. It can be efficacious for complex vascular malformations including lymphatic malformations and the Kasabach-Merritt phenomenon.
Sirolimus has also been shown to have a reduced risk of SCC development in transplant patients. It can, however, cause drug induced acne. Cyclosporine, Azathioprine, Prednisone, and Mycophenolate all increase SCC risk.
101- What medication works via inhibition of the same enzyme as crisaborole ointment 2%?
A. Acitretin
B. Methotrexate
C. Cyclosporine
D. Apremilast
E. Ixekizumab
Correct choice: D. Apremilast
Explanation: Crisaborole is a phosphodiesterase 4 (PDE-4) inhibitor. PDE-4 inhibition results in increased intracellular cyclic adenosine monophosphate (cAMP) levels. The specific mechanism(s) by which crisaborole exerts its therapeutic action for the treatment of atopic dermatitis is not well defined.
102- In addition to tuberculosis screening, what yearly screening for patients on biologic medication should you consider if you are practicing in Arizona?
A. Paracoccidioidomycosis
B. Histoplasmosis
C. Blastomycosis
D. Melioidosis
E. Coccidioidomycosis
Correct choice: E. Coccidioidomycosis
Explanation: Yearly screening IgG and IgM serum testing for coccidioidomycosis should be performed in addition to yearly PPD or Quantiferon Gold test for tuberculosis screening for patient populations in endemic areas such as Arizona. The remaining choices are incorrect.
103- Concomitant administration of retinoid or ketoconazole with doxorubicin may lead to which side effect?
A. Dermatomyositis-like reaction
B. Papulopustular eruption
C. Capillary leak syndrome
D. Sticky skin
E. Leg ulcers
►D
Doxorubicin when given with retinoids or ketoconazole may lead to sticky skin. A dermatomyositis-like reaction and leg ulcers may be seen with hydroxyurea. Epidermal growth factor receptors such as erlotinib and cetuximab can produce papulopustular eruptions. Capillary leak syndrome is seen with interleukins.
104 -Which of the following vehicles is correctly defined
A. Ointment-water in oil emulsion
B. Gel-oil in water emulsion
C. Cream-Semisolid emulsion in alcohol base
D. Lotion/Solution-Cream in water
E. Foam - powder in cream
►A
Various vehicles are used for different clinical situations. Ointments are water in oil emulsions. Creams are oil in water emulsion. Gels are semisolid emulsion in alcohol base .
Lotions/Solutions are powder in water (some oil). Foams are liquid and/or solid materials in a gaseous medium.
105 -Which of the following supplements is most likely to decrease hemolysis associated in patients taking dapsone?
A. Vitamin A
B. Vitamin B6
C. Folic acid
D. Vitamin D
E. Vitamin E
►E
Adverse effects from dapsone are both pharmacologic and idiosyncratic and include hemolytic anemia, methemoglobinemia, agranulocytosis, hypersensitivity syndrome and neuropathy. Of these, the first two are pharmacologic and anticipated, to some degree, in most patients treated with dapsone. However, the magnitude of toxicity varies greatly among individuals on the drug.
Methemoglobinemia is the formation of methemoglobin in the blood, which has a decreased oxygen-carrying capacity compared with hemoglobin and can result in cyanosis. The reaction is related to the N-hydroxy metabolites of dapsone, which are potent oxidants. G6PD-deficient individuals are more susceptible to oxidative stresses, including those from dapsone metabolites, and a baseline G6PD level is recommended prior to initiation of dapsone therapy. Vitamin E (800 IU/day) has been suggested to provide a small amount of protection against methemoglobinemia and hemolysis, however, the clinical benefit of this strategy is unclear.
106 -Potentially fatal ventricular arrhythmias can occur with concomitant use of cisapride and:
A. Astemizole
B. Digoxin
C. Terbinafine
D. Erythromycin
E. Atorvostatin
►D
Co-administration of erythromycin with the antihistamines terfenedine and astemizole or the gastrointestinal promobility agent cisapride increases the risk of torsade de pointes and is contraindicated. These drugs are no longer available in the US.
107- Fomivirsen is a single-stranded antisense oligonucleotide FDA-approved for the treatment of:
A. HSV infection
B. HIV infection
C. EBV infection
D. CMV infection
E. HPV infection
►D
Fomiversen (Vitraene) represents a new class of therapeutic agents known as antisense drugs. It is indicated for the treatment of CMV retinitis in patients with AIDS. The most common adverse effects are ocular inflammation and increases in intraocular pressure.
108- All of the following agents exert their function in a cell-cycle specific manner except:
A. Cyclophosphamide
B. Methotrexate
C. Azathioprine
D. Hydroxyurea
E. 5-fluorouracil
►A
Cyclophosphamide is a cell-cycle nonspecific agent, which produces DNA cross-linkages at any point in the cell cycle. Methotrexate, azaithioprine, and hydroxyurea are S -phase specific cytotoxic agents. 5-fluorouracil is a cell-cycle specific pyrimidine antagonist.
109 -All of the following drugs are known to cause pseudoporphyria except for:
A. Dapsone
B. Tetraycycline
C. Amiodarone
D. NSAIDs
E. Ampicillin
►E
All of the following drugs cause pseudoporphyria except ampicillin. Dapsone, tetracycline, amiodarone, NSAIDs, and nalidixic acid.
110- Thryoid function tests should be checked before and during therapy with which of the following medications?
A. Colchicine
B. Gold
C. Potassium iodide
D. Thalidomide
E. Azathioprine
►C
The Wolff-Chaifkoff effect, which is the inhibition of thyroid hormone synthesis from excess iodides which block organic iodides from binding in the thyroid, can be observed in patients on potassium iodide therapy. In patients with normal thyroid function, autoregulatory mechanisms allow for appropriate escape from this effect. In patients with impaired autoregulatory mechanisms, the Wolff-Chaikoff effect can lead to hypothyroidism.
111- The antihistamine with strong H1 and H2 blockade is:
A. Chlorpheniramine
B. Cetirizine
C. Cimetidine
D. Cyproheptadine
E. Doxepin
►E
Doxepin, a tricyclic antidepressant, has H1 and H2 antihistamine activity.
112 -Which of the following is an adverse effect of oral retinoid therapy?
A. Mania
B. Fibroydysplasia ossicficans progressiva
C. Vascular calcification
D. Hypertension
E. Hypertrichosis
►B
Adverse effects of oral retinoid therapy: Cutaneous: Xerosis, palmoplantar digital desquamation, retinoid dermatitis, photosensitivity, pyogenic granulomas, stickiness sensation, Staph aureus infxns Hair: Teolgen effluvian, abnormal hair texture, dryness Nails: Fragility with nail softening, paronychia, onycholysis Occular: Dry eyes w/visual blurriness, Blepharoconjunctivitis, Photophobia Oral: Cheilitis, dry mouth, sore mouth and tongue Nasal: Nasal mucosal dryness, decreased mucous secretion, epistaxis Musculoskeletal: Arthralgias, myalgias, fatigue and muscle weakness, tendinitis Neurological: Headache, mild depression Gatrointestinal: N/V/D, adb pain
113- In regards to liposuction, what is the maximum amount of tumescent anesthesia (lidocaine) recommended for an adult?
A. 15 mg/kg
B. 25 mg/kg
C. 35 mg/kg
D. 45 mg/kg
E. 55 mg/kg
►E
Technically, 35 mg/kg is considered the safe and average amount recommended. However, maximum amount of lidocaine has been reported to be 55 mg/kg. Tumescent anesthesia is a method where dilute lidocaine is injected into subcutaneous fat for the liposuction procedure.
114- Finasteride is a specific inhibitor of:
A. Dihydrotesterone reductase
B. Type I 5 alpha reductase
C. Type II 5 alpha reductase
D. Aromatase
E. Testosterone synthetase
►C
Finasteride, a type II 5 alpha reductase inhibitor, given as a 1mg tablet daily, is effective in preventing further hair loss and in increasing the hair counts to the point of cosmetically appreciatable results in men ages 18 to 41 with mild to moderate hair loss at the vertex, in the anterior midscalp, and the frontal region.
115- This medication is used for the treatment of scabies in pregnant women:
A. Precipitated sulfur 6%
B. Thiabendazole
C. Malathion
D. Ivermectin
E. Permethrin
A
Precipitated sulfur 6% can be used for the treatment of scabies in pregnant women. Scabies can be in bedding and in clothes and should be washed in hot water after the patient is treated.
116 -Women with unwanted hair have the option of using a cream to help in the reduction of facial hair. This cream is:
A. Eflornithin
B. Spironolactone
C. Finasteride
D. Hydroxy-progesterone
E. Androstenedione
►A
Women that have unwanted facial hair can use eflornithine and is also known as Vaniqa. It is applied to the skin for the reduction of unwanted facial hair. It inhibits ornithine decarboxylase located in the root of the hair follicle.
117 -This antifungal medication has a side effect of causing rare fulminant hepatitis risk, gynecomastia and impotence:
A. Terbinafine
B. Itraconazole
C. Fluconazole
D. Griseofulvin
E. Ketoconazole
►E
Ketoconazole causes rare fulminant hepatitis risk, gynecomastia, and impotence. It inhibits CYP 450 and is a triazole and a keratinophilic.
118- All of the following cause a SLE like eruption except:
A. Anticonvulsants
B. Isoniazid
C. Hydralazine
D. Minocycline
E. Phenophalein
►E
Phenophalein is an ingredient in laxatives and causes fixed drug eruption. Anticonvulsants, Isoniazid, hydralazine, minocycline, procainamide, penicilline, and D-penicillamine all cause SLE- like eruption.
119 -This drug chelates polyvalent cations resulting in the inhibition of the metal dependent enzymes that degrade peroxides in the fungal cell wall:
A. Ciclopirox
B. Griseofulvin
C. Nystatin
D. Terbinafine
E. Itraconazole
►A
Ciclopirox chelates polyvalent cations resulting in the inhibition of metal dependent enzymes that degrade peroxides in the fungal cell wall.
120- Which of the following antifungal agents is contraindicated in patients with a history of porphyria?
A. Griseofulvin
B. Ketoconazole
C. Fluconazole
D. Itraconazole
E. Terfinafine
►A
Griseofulvin has been reported as a potential exacerbator of acute intermittent porphyria, and thus is contraindicated in patients with a history of porphyria.
121- All the following have been known to cause acute generalized exanthematous pustulosis except:
A. Beta-lactam antibiotics
B. Macrolide antibiotics
C. Mercury
D. Cephalosporins
E. Hydrochlorothiazides
►E
Hydrochlorothiazide causes a lichenoid eruption. Beta-lactam antibiotics, macrolide antibiotics, Mercury, and cephalosporins all have been known to cause AGEP.
122- Which of the following has been associated with a lichenoid drug eruption?
A. Dabigatran
B. Hydrochlorothiazide
C. Acetaminophen
D. Erythromycin
E. Nicotinamide
►B
Lichen-planus-like (lichenoid) drug eruptions have been reported with: antimalarials, B-blockers, captopril, gold, penicillamine, HCTZ, NSAIDs. Lichenoid drug reactions are often photodistributed.
123- Which of the following is true of the live attenuated varicella vaccine when given to healthy adults?
A. It was marginally effective
B. It provides only short term protection (6 months)
C. It protects even individuals who never had serconversion or whose antibody levels were undetectable from severe varicella zoster viral disease
D. The disease process will be accelerated
E. Disseminated zoster is frequently seen
►C
When live attenuated varicella vaccine is given to healthy adults, it protects even individuals who never had serconversion or whose antibody levels were undetectable from severe varicella zoster viral disease.
124- The steroid with the least minerocorticoid activity is:
A. Hydrocortisone
B. Cortisone
C. Prednisone
D. Methylprednisolone
E. Prednisolone
►D
Of the corticosteroids listed, the steroid with the lowest mineralcorticoid activity is methylprednisolone. Minerocorticoids act on the kidney to decrease the rate of sodium excretion (with accompanying retention of water). Triamcinolone, dexamethasone, and betamethasone also have low mineralcorticoid activity.
125 -Which of the following is a low sedation metabolite of hydroxyzine?
A. Fexofenadine
B. Cetirizine
C. Loratadine
D. Cyproheptadine
E. Ranitidine
►B
Cetirizine is a second-generation H1 antihistamine that is a low sedation metabolite of hydroxyzine.
126- Gold is used for its anti-inflammatory effects and inhibits macrophage and neutrophil phagocytosis. It is effective in inhibiting degradative epidermal lysosomal enzymes which contribute to blister formation. This reaction that can occur with gold causes acute flushing, dizziness, hypotension and fainting:
A. Nitritoid reaction
B. Leucovorin reaction
C. Juxheimer reaction
D. Golden reaction
E. Lupus like reaction
►A
Nitritoid reaction is after a gold injection that causes acute flushing, dizziness, hypotension, and fainting. Gold is used in treat severe lupus erythematosus and psoriatic arthritis. The most common reaction is mucocutaneous side effects such as stomatitis, cheilitis and li chen planus like eruptions and pityriasis rosea like eruptions.
127- What family of medications is associated with xerosis?
A. Sulfonylureas
B. Beta blockers
C. Calcium channel blockers
D. Loop diuretics
E. Cholesterol lowering agents
►E
Medications that alter the lipid composition of the epidermis and stratum corneum may impair the normal barrier function of the skin. Cholesterol lowering medications like HMG-CoA reductase inhibitors and niacin may cause xerosis through this mechanism.
128 -Which of the following is the highest potency topical corticosteroid?
A. Halobetasol propionate cream 0.05%
B. Triamcinolone acetonide ointment 0.1%
C. Fluocinolone acetonide cream 0.025%
D. Hydrocortisone valerate ointment 0.2%
E. Mometasone furoate ointment 0.1%
►A
Halobetasol propionate cream 0.05% is a superpotent Class 1 topical steroid. Triamcinolone acetonide ointment 0.1% and hydrocortisone valerate ointment 0.2% are medium potency class 4 topical steroids. Fluocinolone acetonide cream 0.025% is a medium potency class 4 topical steroid. Mometasone furoate ointment 0.1% is a high potency class 2 topical steroid.
129- Which of the following substances is not found in Castellani’s paint?
A. Resorcinol
B. Acetone
C. Magenta
D. Phenol
E. Lactic acid
►E
Castellani’s paint is a fungicidal and bactericidal agent. It contains boric acid, resorcinol, acetone, water, industrial methylated spirit, magenta, and phenol. Magenta may stain clothing and skin while phenol may be toxic in children.
130- Which of the following locations has the highest percutaneous absorption of topical corticosteroids?
A. Scrotum
B. Axilla
C. Back
D. Arm
E. Palm
c
►A
Absorption through the scrotum is about 42 times greater than the ventral forearm. Although less, other occluded sites such as the axilla have increased percutaneous absorption. The palms and soles have the least due to the thick stratum corneum.
131 -A patient is using imiqimod for her warts. This medicine uses which toll like receptor to act on:
A. 2
B. 3
C. 9
D. 5
E. 7
►E
Imiquimod acts on toll like receptor 7. It can be used in the treatment of warts, actinic keratosis, superficial basal cell carcinomas and squamous cell carcinomas in-situ. It also up-regulates TNF alpha, IFN gamma and alpha and IL-12.
132- Approximately what percentage of patients with drug hypersensitivity syndrome will have liver function test abnormalities?
A. Less than 10%
B. 25%
C. 50%
D. 75%
E. Close to 100%
►C
Drug hypersensitivity syndrome is characterized by fever, skin eruption and internal organ involvement. Drugs associated with drug hypersensitivity syndrome include sulfonamindes, dapsone, anticonvulsants (carbamezapine, phenobarbitol, lamotrigine), anti-retrovirals (ritonovir, nevirapine) and minocycline. Approximately 50% of patients will have abnormal liver enzymes.
133 -Which of the following biologic therapies is pregnancy category C?
A. Etanercept
B. Alefacept
C. Infliximab
D. Efalizumab
E. Adalimumab
►D
All of the above drugs are pregnancy category B except efalizumab which is category C.
134- Patients that are on methotrexate with renal disease and also using NSAIDs or TMP/SMX with no folate supplementation are at a greater risk for:
A. Pancytopenia
B. Liver fibrosis
C. Liver cirrhosis
D. Renal failure
E. Renal insufficiency
►A
Patients on methotrexate with renal disease and on NSAIDs and TMP/SMX with no folate supplementation are at a great risk for pancytopenia. Leukovorin is given under conditions of methotrexate induced myelosuppression.
135 -Which of the following side effects has not been reported in association with intravenous immune globulin?
A. Headache
B. Flushing
C. Hypotension
D. Stevens-Johnson syndrome
E. Anaphylaxis
►D
IVIG is used to treat several diseases including graft versus host disease, connective tissue disease, and autoimmune bullous dermatoses. Adverse effects include infusion reactions (headache, flushing, chills, myalgia, wheezing, Tachycardia, lower back pain, nausea, or hypotension). Anaphylaxis occurs rarely. Disseminated intravascular coagulation, transient neutropenia, and aseptic meningitis syndrome has been reported. Cutaneous adverse effects include eczematous eruptions and alopecia.
c
136 -The Wolff-Chaikoff effect is associated with what medication?
A. Bexarotene
B. Zidovudine
C. Potassium iodide
D. Hydroxychloroquine
E. Thalidomide
►C
The Wolff-Chaikoff effect is the inhibition of thyroid hormone synthesis from excess iodides which block organic iodides from binding in the thyroid. In patients with normal thyroid function, autoregulatory mechanisms allow for escape from this effect. In patients with impaired autoregulatory mechanisms, the Wolff-Chaikoff effect can lead to hypothyroidism. Thyroid function should be evaluated and monitored with patients started on potassium iodide.
137 -This patient also has a diagnosis of acne vulgaris (diagnosed 10 years ago). What is the most likely explanation for these cutaneous changes?
A. Peripheral vascular disease
B. Diabetes mellitus
C. Drugs hypersensitivity reaction to penicillin
D. Minocycline-induced hyperpigmentation
E. Leukocytoclastic vasculitis
►D
This patient has minocyclin-induced hyperpigmentation. Hyperpigmentation is one of the most commonly observed side effects of minocycline and occurs regardless of dosage or treatment duration (although most often seen in patients after long-term treatment with the drug). Three distributions can be seen: Type I (blue-black pigmentation in sites of inflammation/scars), Type II (blue-black pigmentation on the anterior lower legs, and Type III (muddy brown diffuse pigmentation on normal, sun-exposed skin). This patient has Type II pigmentation.
138- A female patient with adult acne is placed on spironolactone for her acne vulgaris. As a physician, you warn her that there is a black box warning against patients with a :
A. Personal history of breast cancer
B. Personal history of thyroid cancer
C. Personal history of bladder cancer
D. Personal history of colon cancer
E. Personal history of rectal cancer
►A
Spironolactone is an antiandrogenic potassium sparing diuretic. It can be used for women with adult acne that is recalcitrant to treatment. Although it is not first line, it helps to block androgens that cause acne in the jawline. Spironolactone has a black box warning against patient with a personal history of breast cancer or family history of breast cancer.
139 -Clinical evidence of hypothyroidism can be induced by which drug?
A. Bexarotene
B. Gold
C. Griseofulvin
D. Acitretin
E. Isotretinoin
►A
Bexarotene can cause a central hypothyroidism with low TSH and T4. You must titrate the levothyroxine dose to the free T4 as it is a central hypothyroidism which is defined as insufficient TSH to stimulate an otherwise normal thyroid gland.
140- All of the following are true regarding water-soluble retinoids EXCEPT:
A. They are undetectable in the serum after 1 month of stopping therapy
B. They include isotretinoin
C. They include etretinate
D. They include bexarotene
E. They have very little lipid deposition
►C
Isotretinoin, acitretin, and bexarotene are water-soluble, with very little lipid deposition. Etretinate is 50 times more lipophilic than acitretin, with increased storage in adipose tissue.
141- Which of the following may cause an acneiform eruption?
A. Fluoxetine
B. Valproic acid
C. ACTH
D. Finasteride
E. Methotrexate
►C
Many medications are associated with acneiform eruptions, including halogens (bromide and iodide), androgenic hormones such as testosterone, ACTH, corticosteroids, isoniazid (INH), lithium, phenytoin, and vitamins B2, B6 and B12.
142- Peak vulnerability to thalidomide occurs between which days of gestation?
A. Days 1-14
B. Days 15-20
C. Days 21-36
D. Days 37-56
E. Days 57-70
►C
Peak vulnerability to thalidomide occurs between days 21 to 36 of gestation, during which only a single dose will cause birth defects to occur. Birth defects associated with thalidomide include phocomelia (underdevelopment of arms and legs, the most common birth defect), ear malformation, and gastrointestinal and urogenital defects.
143- Which of the following drugs is correctly matched to its target enzymes?
A. Tacrolimus-Thymidine kinase
B. Methotrexate-Inosine monophosphate dehydrogenase
C. Mycophenolate Mofetil-Phospholipase A2
D. Acyclovir-DNA polymerase
E. Terbinafine-Cytochrome p450
►D
Drug/Specific enzyme inhibited Tacrolimus - Calcineurin Methotrexate - Dihydrofolate reductase Mycophenolate mofetil - Inosine monophosphate dyhydogenase Acyclovir - DNA Polymerase Terbinafine - Squalene epoxidase
144- Which of the following drugs has been known to cause pyogenic granuloma?
A. Daunorubicin
B. Mithramycin
C. Isosfamide
D. Capecitabine
E. Paclitaxel
►D
Systemic retinoids, indinavir and capecitabine have all been describe to cause pyogenic granulomas.
145- Which biologic agent is administered intramuscularly?
A. Alefacept
B. Efalizumab
C. Etanercept
D. Infliximab
E. None of the above
►A
Alefacept is given intramuscularly.
146 -Which chemotherapeutic agent has been reported to cause acral sclerosis with Raynaud’s phenomenon?
A. Bleomycin
B. 5-Fluorouracil
C. Methotrexate
D. Actinomycin
E. Interferon
►A
Bleomycin is an antibiotic that induces single strand breaks in the DNA. Reactions to bleomycin include flagellae hyperpigmentation, acral sclerosis with Reynaud’s, penile calcification, and a morbilliform eruption. Etreinate is stored in the lipid for years and can be re-esterified to acitretin after ETOH. It should not be used for women that are wanting to get pregnant because it can be stored in the fat for years.
147- The retinoid that is stored in lipid for years and can be re-esterified as acitretin with ETOH is:
A. Etretinate
B. Acitretin
C. Tretinoin
D. Isotretinoin
E. Bexarotene
►A
Etreinate is stored in the lipid for years and can be re-esterified to acitretin after ETOH. It should not be used for women that are wanting to get pregnant because it can be stored in the fat fo r years.
148- Bone marrow suppression can occur more often in individuals taking azathioprine with genetically low allele activity of what enzyme?
A. Inosine monophosphate dehydrogenase
B. Thiopurine methyltransferase
C. Glucose-6-phosphatase
D. Dihydrofolate reductase
E. Epoxide hydroxylase
►B
Thiopurine methyltransferase is one of three enzymes that metabolize azathioprine along with xanthine oxidase and HGPRT. Decreased activity of TPMT leads to heightened metabolism by HGPRT into the active 6-thioguanine. This may lead to increased toxicity including bone marrow suppression.
149 -Cefaclor has been associated with increased incidence of what in children?
A. Mononucleosis-like syndrome
B. Anaphylaxis
C. Transaminitis
D. Serum sickness reaction
E. Generalized tonic-clonic seizures
►D
The use of cefaclor has been associated with an increased incidence of serum sickness in children.
150 -Methotrexate can cause hepatotoxicity and uncommonly cause acute pneumonitis. The cumulative doses at or above this amount can have an increase risk for inducing liver fibrosis and cirrhosis:
A. 2.0 grams
B. 3.0 grams
C. 4.0 grams
D. 5.0 grams
E. 6.0 grams
►C
Methotrexate is an antimetabolite that can be used for psoriasis and immunobullous diseases. At a cumulative dose at or above 4.0 grams can risk inducing liver fibrosis and cirrhosis. The liver biopsy is the gold standard diagnostic test.
151 -Which of the following chemotherapeutic agents has been linked to acneiform eruptions?
A. Bleomycin
B. Cytarabine
C. Cisplatin
D. Doxorubicin
E. Cetuximab
►E
Cetuximab is a chimeric anti-epidermal growth factor receptor antibody that is FDA approved to treat advanced colorectal cancer. Acneiform eruptions have been reported to occur in up to 1/3 of patients.
152- Neutrophilic eccrine hidradenitis is a side effect of which therapeutic agent?
A. Interferon-alpha
B. Cytarabine
C. Interferon type I
D. Intravenous immune globulin
E. Granulocyte colony stimulating factor
►B
Neutrophilic eccrine hidradenitis most commonly occurs in the setting of a patient with acute myelogenous leukemia being treated with cytarabine. Clinical manifestations include tender, erythematous macules, papules and plaques on the trunk, neck and extremities which resolve within a few days. Histologically, this drug eruption is defined by the presence of dense neutrophilic infiltrate within and around eccrine glands, with necrosis of eccrine epithelial cells.
153- Cyclosporin A should not be consumed with grapefruit juice due to:
A. Induction of CYP2D6 by grapefruit juice
B. Inhibition of CYP2D6 by grapefruit juice
C. Induction of CYP3A4 by grapefruit juice
D. Inhibition of CYP3A4 by grapefruit juice
E. Grapefruit juice binds cyclosporine, inactivating it in the GI tract.
►D
Grapefruit juice is an inhibitor of CYP3A4 at the intestinal mucosal membrane. The intestinal CYP3A4 is involved in “first pass” metabolism - thus with inhibition of this enzyme in the gut, less cyclosporine is metabolized, allowing for greater absorption of cyclosporine. Saquinivir also can be affected by this “first pass” inhibition by grapefruit juice.
154- Which of the following statements regarding dapsone and sulfapyridine is true?
A. They exert their anti-inflammatory actions by stimulating the myeloperoxidase activity of polymorphonuclear leukocytes
B. Dapsone hypersenstivity syndrome is characterized by lymphocytosis
C. Sulfapyridine has a similar but often more severe side effect profile than dapsone
D. Concomittant administration of cimetidine has been shown to increase the risk of methemoglobinemia
E. None of these answers are correct (all are false)
►E
None of the above statements are true. Dapsone and sulfapyridine exert their anti-inflammatory actions by inhibiting the myeloperoxidase activity and chemotactic abilities of polymorphonuclear leukocytes. Dapsone hypersenstivity syndrome is characterized by eosinophilia, as well as a severe mononucleosis-like reaction, including fever, erythroderma, hepatitis, and even death. Sulfapyridine has a similar but often less severe side effect profile. Cimetidine has been shown to provide some protection against methemoglobin formation.
155 -All of the following retinoids are excreted in the urine EXCEPT:
A. Bexarotene
B. Etretinate
C. Isotretinoin
D. Tretinoin
E. Acitretin
►A
Bexarotene is excreted via hepatobiliary excretion. The others are excreted in bile and urine.
156 -Which drug has been associated with cholestatic hepatitis?
A. Clindamycin
B. Erythromycin
C. Rifampin
D. Doxycycline
E. Ampicillin
►B
The estolate form of erythromycin has been associated with cholestatic hepatitis.
157 -A patient taking daily prednisone is advised to switch to alternate day dosing to decrease the risk of:
A. Glaucoma
B. Aseptic bone necrosis
C. Cataracts
D. Adrenal crisis
E. Osteoporosis
►D
Long-term therapy with oral corticosteroids can result in numerous adverse effects, including elevated risks of glaucoma, cataracts, hypertension, diabetes, osteoporosis, adrenal axis suppression, and aseptic bone necrosis. Alternate-day dosing or oral corticosteroids lowers the rate of adrenal axis suppression. It is hypothesized that during the off day, cell mediated immunity, white blood cells subset levels, and potassium excretion are normalized while the anti-inflammatory benefits of the drug persist. Alternate-day corticosteroid therapy should be employed once adequate disease control has been attained with daily dosing. Of note, the risk of cataracts, osteoporosis, and other adverse effects of long-term corticosteroid use are not minimized with alternate-day dosing.
158- The mechanism of action of mycophenolate mofetil most closely resembles that of what other drug?
A. Cyclophosphamide
B. Doxorubicin
C. Azathioprine
D. Hydroxyurea
E. Chlorambucil
►C
Both azaithioprine and mycophenolate mofetil directly interfere with purine synthesis.
159- The form of erythromycin most likely to cause jaundice is:
A. Ethylsuccinate
B. Estolate
C. Stearate
D. Gluceptate
E. Lactobionate
►B
The form of erythromycin that most likely causes jaundice is estolate.
160 -Which cell type is increased by glucocorticoids?
A. Neutrophils
B. Monocytes
C. T-cells
D. B-cells
E. Eosinophils
►A
Glucocorticoids alter the balance of circulating leukocytes, causing an increase in the number of polymorphonuclear leukocytes and diminishing the numbers of lymphocytes, eosinophils, and monocytes.
161 -This antiviral medicine doesn’t require phosphorylation and may be used for acyclovir recalcitrant disease:
A. Foscarnet
B. Gancyclovir
C. Famciclovir
D. Valacyclovir
E. Penciclovir
►A
Foscarnet is a non-competitive inhibitor of viral DNA polymerase. It does not require phosphorylation and can be used for acyclovir recalcitrant disease.
162- A patient taking azathioprine for bullous pemphigoid develops a hypersensitivity syndrome characterized by fever and shock. Approximately how long ago did the patient start this medication?
A. 14 days
B. 24 hours
C. 3-4 days
D. 6 weeks
E. 1 week
►A
Azathioprine is a purine analog which is used to treat multiple inflammatory disorders, including autoimmune bullous disease, vasculitis, and severe dermatitis. A hypersensitivity syndrome with fever and shock can occur at around 14 days.
169- Which of the following medications is most likely to have caused this reaction?
A. Pseudoephedrine hydrochloride
B. Vancomycin
C. Lithium
D. ACE inhibitor
E. Diclofenac
►A
Fixed drug eruptions occur 30 mintues to 8 hours after ingestion of offending agent. After rechallenge with the same agent, the fixed drug eruption will recur. Potential causes of a fixed drug eruption include analgesics, sulfonamides, barbituates, pseudoephedrine and anticonvulsants. Pseudoephedrine causes non-pigmented fixed drug as shown in the photo.
224- Over use of of which medication may lead to this clinical image?
A. Topical steroid
B. Topical antibiotic
C. Calcipotriene
D. Imiquimod
E. Hydroquinone
►E
Exogenous ochronosis has been reported with prolonged use of high concentration hydroquinone. On pathology, a characteristic ochre colored deposit is noted between the collagen bundles.
365 -Which member of the tetracycline family is most likely to have caused this photomediated reaction?
A. Demeclocycline
B. Doxycycline
C. Minocycline
D. Oxytetracycline
E. Tetracycline
►A
The tetracycline family of antibiotics are bacteriostatic and act by inhibiting protein synthesis. Each member of the family may cause photosensitivity, but demeclocycline is the most photosensitizing.
400- Which treatment for this condition can cause CNS toxicity?
A. Permethrin
B. Malathion
C. Precipitated sulfur
D. Lindane
E. Ivermectin
Correct choice: D. Lindane Explanation: This is scabies.
Management of a scabies outbreak involves the identification and treatment of individual patients and household contacts with insecticides. Oral antibiotics are required for secondary infection. Careful attention to instructions is essential if scabies is to be cured.
The chemical insecticides used to treat scabies are called scabicides. The scabicide is applied to the whole body from the scalp to soles. The usual topical treatment is 5% permethrin cream, left on the entire skin for 8–10 hours. It should be applied under fingernails using a soft brush.
Oral ivermectin 200 mcg/kg is convenient, but more expensive than topical permethrin. It may be slightly less effective. It is mainly used for mass treatments in institutions, or in patients unable to use topical therapy.
Gamma benzene hexachloride cream is no longer recommended or available due to neurotoxicity; it is also a suspected carcinogen and is no longer marketed in New Zealand.
Other proven treatments include:
- 0.5% aqueous malathion lotion, left on for 24 hours
- 25% benzyl benzoate lotion, applied daily for 3 days. This is irritant, and should not be used in children.
- 2–10% precipitated sulphur ointment
Treatment should be repeated after 8–10 days after the first application to catch mites that have newly hatched. Crotamiton cream can be used to reduce itch; it is a weak scabicide. Patients with crusted scabies may need repeated oral and topical treatments over several weeks or longer.
Contacts must be identified and treated. In addition:
-Bed linen, towels and clothing should be laundered after treatment.
-Non-washable items should be sealed in a plastic bag and stored for one week.
-Rooms should be thoroughly cleaned with normal household products. Fumigation or specialized cleaning is not required.
-Carpeted floors and upholstered furniture should be vacuumed.
405- Which of the following drugs produces a muddy brown pigmentation classically in sun- exposed areas?
A. tetracycline
B. minocycline
C. doxycycline
D. demeclocycline
E. cephalexin
Correct choice: B. minocycline
Explanation: Minocycline does not typically lead to overt phototoxicity but may cause diffuse “muddy brown” hyperpigmentation that is accentuated in sun-exposed areas as well as bluish discoloration of scars (including those due to acne) and normal skin (in particular on the shins). The muddy brown hyperpigmentation presents with increased melanin at the basal layer and within macrophages on histopathology.
