Pharm 151 - 200 Flashcards
Which antiparasitic agent is highly flammable?
1 Lindane
2 Permethrin
3 Precipitated sulfur
4 Thiabendazole
5 Malathion
Malathion, an organophosphate cholinesterase inhibitor used to treat scabies and head lice, is flammable.
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What is the recommended period for contraception after cessation of acitretin therapy in the United States?
1 1 month
2 3 months
3 1 year
4 2 years
5 3 years
Etretinate has a prolonged half-life of 80-160 days. The levels may persist up to 3 years in the body. Acitretin can be converted to etretinate in the presence of ethanol.
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Painful periungual pyogenic granulomas have been associated with what medication?
1 Ketoconazole
2 Indinavir
3 Doxycycline
4 Tazarotene
5 Valacyclovir
Periungual pyogenic granulomas and painful paronychial eruptions have been reported in association with various anti-HIV medications including, indinavir, zidovudine, and lamivudine.
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Need photo #154
Which member of the tetracycline family is most likely to have caused this photomediated reaction?
1 Demeclocycline
2 Doxycycline
3 Minocycline
4 Oxytetracycline
5 Tetracycline
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.
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Gray-green discoloration of the mid-portion of permanent teeth is a side effect of?
1 Doxycycline
2 Tetracycline
3 Minocycline
4 Fluoroquinolones
5 clindamycin
In contrast to tetracycline staining of the teeth, which occurs in childhood and produces a brown discoloration along the gingival third, minocycline stains the permanent teeth in adults, with a gray-green discoloration of the mid-portion of the tooth.
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A 59 year-old woman is diagnosed with acute myelogenous leukemia. Induction chemotherapy is initiated. A few days later the patient develops tender erythematous plaques on her face. What is the most likely culprit drug?
1 Methotrexate
2 Cytarabine
3 5-fluorouracil
4 Cyclophosphamide
5 Hydroxyurea
The most likely diagnosis is neutrophilic eccrine hidradenititis. Cytarabine is the usual offending agent.
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Neutrophilic eccrine hidradenitis is associated most often with which chemotherapeutic agent?
1 5-fluorouracil
2 Cytarabine
3 Dactinomycin
4 Doxorubicin
5 Vinca alkaloids
Neutrophilic eccrine hidradenitis occurs in neutropenic patients with malignancies, usually acute myelogenous leukemia. Cytarabine is the most commonly associated medication.
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Which antihistamine has suppressor T-cell inhibitory activity?
1 Doxepin
2 Promethazine
3 Fexofenadine
4 Cimetidine
5 Cromolyn sodium
Cimetidine is an H2 antihistamine that has suppressor T-cell inhibitory activity, by competitively blocking their H2 receptors. Immunomodulatory effects are useful for treating mucocutaneous candidiasis, verruca vulgaris, and condyloma acuminata.
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Which of the following medications would you not want a woman using an IUD as her only source of contraception to take?
1 Ibuprofen
2 Cefalexin
3 Etanercept
4 Infliximab
5 Lidocaine
NSAIDS (including ibuprofen) and Azathiprine have been associated with IUD failure. The other listed medications are all pregnancy category B and should be safe for use in this patient.
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Vascular leak syndrome has been associated with which chemotherapeutic agent?
1 Denileukin diftitox
2 Cytarabine
3 Methotrexate
4 Bleomycin
5 Interferon
Denileukin difitox (brand name Ontak) is approved for the treatment of cutaneous T-cell lymphoma. Denileukin difitox is a fusion protein composed from a portion of IL-2 with diphtheria toxin. The chemotherapy is taken up by cells expressing high-affinity IL-2 receptors. Capillary leak syndrome presenting with hypotension, edema, pleural effusions, and weight gain caused by fluid retention has been reported in patients receiving denileukin difitox. Q/Q(M)-477151 Report a Problem
Which of the following statements regarding podophyllin is NOT correct?
1 It is derived from the May apple plant
2 It binds tubulin
3 It arrests cells in telophase
4 It is contraindicated in pregnancy
5 None (all of these statements are true)
Podophyllin is a crude cytotoxic extract from the May apple plant. It is antimitotic, arresting cells in metaphase (not telophase) by binding to the protein tubulin. It may be teratogenic and should not be used in pregnancy.
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Which of the following statements regarding drug interactions is true?
1 Drugs that induce CYP3A enzymes may decrease levels of drugs which act as substrates for CYP3A
2 CYP3A inhibitors may increase levels and cause toxicity of drugs metabolized by cytochrome P-450
3 Terbinafine is not metabolized by cytochrome P-450
4 Tobacco induces P-450 enzymes
5 All of the above are true
The most relevant drug interactions in dermatology involve the hepatic biotransformation pathways catalyzed by the cytochrome P-450 isoenzymes from the subfamilies CYP3A3/4. Drugs that induce CYP3A enzymes may decrease levels of drugs which act as substrates for CYP3A. CYP3A inhibitors may increase levels and cause toxicity of drugs metabolized by cytochrome P-450. Terbinafine is not metabolized by cytochrome P-450, but inhibits CYP2D6-mediated metabolism. Tobacco induces P-450 enzymes.
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The most specific marker of drug-induced lupus is:
1 Anti-histone Ab
2 ANA
3 Anti-Ro Ab
4 Anti-La Ab
5 Anti-ds DNA Ab
Which of the following is true regarding the use of cyclosporine?
1 Guidelines limit the continuous use of cyclosporine in the US to 5 years
2 Cyclosporine should not be used together with methotrexate
3 Cyclosporine is not an effective treatment for psoriatic arthritis
4 Cyclosporine inhibits the activation of antigen presenting cells
5 Cyclosporine has not shown efficacy in the treatment of chronic urticaria
Cyclosporine binds to cyclophilin, an intracellular immunophilin, and inhibits the activity of calcineurin phosphatase, which is then unable to phosphorylate NFAT. Guidelines limit the use of cyclosporine in the US to one year. Cyclosporine is an effective treatment for psoriatic arthritis, alone or in combination with methotrexate. Cyclosporine inhibits the activation of T-cells, NK cells, and antigen presenting cells. And cyclosporine has shown some efficacy in histamine resistant chronic urticaria.
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Clofazamine hyperpigmentation has been described as:
1 Dark hyperpigmented streaks in the nails
2 Red-brown hyperpigmentation within skin lesions
3 Blue-gray hyperpigmentation over the anterior shins, palate, ears
4 Slate gray-purple hyperpigmentation in a photo-exposed distribution
5 Yellow discoloration of the skin, sclera
Clofazamine can induce red-brown hyperpigmentation within skin lesions of patients with Hansen’s disease.
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Which of the following side effects has not been reported in association with intravenous immune globulin?
1 Headache
2 Flushing
3 Hypotension
4 Stevens-Johnson syndrome
5 Anaphylaxis
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, achycardia, 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.
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Cyclosporine forms a complex to directly interfere with activation of what calcium-dependent protein?
1 NFAT-1
2 Calcineurin
3 Calmodulin
4 Cyclophilin
5 Cytochrome P-450
Cyclosporine inhibits calcineurin, a phosphatase activated in the presence of calmodulin and calcium, by cyclophilin. Cyclosporine forms a complex with cyclophilin, blocking its ability to activate calcineurin, and thus preventing calcineurin from phosphorylating NFAT-1, a transcription factor. NFAT-1, when phosphorylated can travel to the nucleus of cells, initiate IL-2 production, and stimulate T-cell proliferation.
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Which antibiotic is the treatment of choice for pregnant patients with Rocky Mountain Spotted Fever?
1 Amoxicillin
2 Doxycycline
3 Erythromycin
4 Chloramphenicol
5 Trimethoprim
Chloramphenicol is the treatment of choice for pregnant patients with Rocky Mountain Spotted Fever. In non-pregnant patients, the treatment of choice is Doxycycline.
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Which of the following oral agents has been effective in the treatment of Norwegian scabies?
1 Thiabendazole
2 Ivermectin
3 Mebendazole
4 Griseofulvin
5 Metroniddazole
Ivermectin (Stromectol) is an anti-helminthic agent currently FDA-approved for the treatment of strongyloides and onchocerciasis. Several publications have reported efficacy of this agent in the treatment of scabies and head lice. Due to its low rate of adverse effects, its high rate of effectiveness, and its ease of administration, some authors consider this agent to be the treatment of choice for scabies and head lice. The mechanism of action of ivermectin is blockade of glutamate-gated, chloride ion channels, with adverse effects on nerve and muscle resulting in paralysis and death of the helminth or mite. The drug has a very low affinity for mammalian chloride channels resulting in its relatively low toxicity. Adverse effects are rare and have been associated with accidental intoxication. It should be avoided when there is compromise of the blood-brain-barrier. Ivermectin is pregnancy category C. There are virtually no associated drug interactions with oral ivermectin therapy.
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The SPF of a sunscreen is based on applying the sunscreen at what concentration?
1 1 mg/cm2
2 2 mg/cm2
3 3 mg/cm2
4 4 mg/cm2
5 5 mg/cm2
A sunscreen SPF is based on using it at a concentration of 2 mg/cm2 which is about 1 ounce or 30 grams for the entire average sized body. It also is about 3-5 grams for the head and neck.
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Which of the following systemic agents has been shown to be the most effective in the treatment of toenail onychomycosis?
1 Ketoconazole
2 Griseofulvin
3 Itraconazole
4 Fluconazole
5 Terbinafine
Craford et al. reviewed the available literature examining the efficacy of systemic anti-fungals and performed a meta-analysis. Pooled analysis of cure rates at 11 and 12 months suggested that terbinafine was more effective than itraconazole.
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Neutrophilic eccrine hidradenitis is a side effect of which therapeutic agent?
1 Interferon-alpha
2 Cytarabine
3 Interferon type I
4 Intravenous immune globulin
5 Granulocyte colony stimulating factor
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, papuls 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.
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What antifungal is known to cause gynecomastia and impotence?
1 Griseofulvin
2 Itraconazole
3 Terbinafine
4 Ketoconazole
5 Fluconazole
Ketoconazole is known to cause gynecomastia and impotence, by interfering with androgen and glucocorticoid synthesis.
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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, papuls 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.
Q/Q(M)-477318 Report a Problem
Which drug may increase levels of digoxin?
1 Amoxicillin
2 Ciprofloxacin
3 Erythromycin
4 Minocycline
5 Cephalexin
Erythromycin inhibits the cytochrome P-450 system, which may result in increased levels of digoxin, among many other drugs.
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Which of the following statements regarding sunscreens is true?
1 Physical blockers absorb ultraviolet light and convert it to lower energy wavelengths
2 Methyl anthranilate is a UVB absorber
3 Padimate O is a UVB absorber
4 Photoallergy has not been reported to benzophenones
5 PABA and its derivates do not cross react with sulfonamides
Physical blockers reflect and scatter UV rays, whereas chemical sunscreens absorb UV light and convert the absorbed energy into longer lower energy wavelengths. Methyl anthranilate is a UVA blocker. Padimate O, a PABA derivative, is a UVB blocker. Photoallergy has been reported with increasing frequency to benzophenones. Allergic contact allergy can occur with PABA and its derivatives, which can cross react with azodyes, aniline, procaine, benzocaine, paraphenylenediamine, and sulfonamides.
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The following drugs have been implicated in drug-induced subacute cutaneous lupus erythematosus:
1 Terbinafine
2 Verapamil
3 Pravastatin
4 All the above are correct
5 None of the above are correct
All of the above choices have been implicated in drug-induced subacute cutaneous lupus erythematosus.
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Cefaclor has been associated with increased incidence of what in children?
1 Mononucleosis-like syndrome
2 Anaphylaxis
3 Transaminitis
4 Serum sickness reaction
5 Generalized tonic-clonic seizures
The use of cefaclor has been associated with an increased incidence of serum sickness in children.
Q/Q(M)-474451 Report a Problem
Which of the following medications mechanism of action is through inhibition of DNA-dependent RNA polymerase?
1 Penicillin G
2 Cephalexin
3 Tetracycline
4 Ciprofloxacin
5 Rifampin
Rifampin is an antibiotic used frequently for M. leprae and M. tuberculosis. It is the only drug bactericidal to M. leprae. Its mechanism of action is by inhibiting RNA synthesis by inhibiting DNA-dependent RNA polymerase. Penicillin G inhibits bacterial cell wall synthesis by blocking the transpeptidation step. Cephalosporins have a similar mechanism of action, possessing a beta-lactam ring. Tetracycline inhibits protein synthesis by binding and inhibiting the 30S ribosome while the fluoroquinolone family inhibits DNA gyrase.
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The t 1/2 of isotretinoin is:
1 1 hour
2 7 hours
3 20 hours
4 2 days
5 120 days
The t 1/2 of isotretinoin is 20 hours. The other answers list the t 1/2 times of various retinoids.
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Which of the following is a side effect of hydroquinone cream?
1 Telangiectasia
2 Photosensitivity
3 Ochronosis
4 Tachyphylaxis
5 Atrophy
Exogenous ochronosis is an uncommon complication of irreversible pigmentation due to overuse of topical hydroquinone (1,4 dihydroxybenzene). Hydroquinone acts to by melanocyte pigment production by auto-oxidation of melanin, tyrosinase and phenol oxidases.
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Of the new biologic therapies for psoriasis, which agent requires weekly CD4 T-cell count monitoring?
1 Efalizumab
2 Alefacept
3 Infliximab
4 Etanercept
5 Adalimumab
Alefacept is a human LFA-3/IgG fusion protein, which blocks LFA-3 on antigen presenting cells from interacting with CD-2 on T-cells, preventing T-cell stimulation. Alefacept also eliminates activated memory-effector T-cells, so weekly CD4 T-cell counts are required.
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Which of the following are retinoid side effects?
1 Reversible hypothyroidism
2 Diffuse interstitial skeletal hyperostosis
3 Premature epiphyseal closure
4 Pseudotumor cerebri
5 All of these answers are correct
Bexarotene has been shown to cause reversible hypothyroidism, not hyperthyroidism. Systemic retinoids have been shown to cause diffuse interstitial skeletal hyperostosis, premature epiphyseal closure, and pseudotumor cerebri (risk increased with concommitant use of tetracyclines).
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Which of the following is true of the live attenuated varicella vaccine when given to healthy adults?
1 It was marginally effective
2 It provides only short term protection (6 months)
3 It protects even individuals who never had serconversion or whose antibody levels were undetectable from severe varicella zoster viral disease
4 The disease process will be accelerated
5 Disseminated zoster is frequently seen
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.
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Finasteride is a specific inhibitor of:
1 Dihydrotesterone reductase
2 Type I 5 alpha reductase
3 Type II 5 alpha reductase
4 Aromatase
5 Testosterone synthetase
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.
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Which of the following agents is NOT a UVA blocker?
1 Dioxybenzone
2 Amyl p-dimethylaminobenzoate
3 Dibenzoylmethane
4 Avobenzone
5 Red veterinary petrolatum
Dioxybenzone is one of the benzophenones (as in oxybenzone and sulisobenzone), which are UVA blockers. Amyl p-dimethylaminobenzoate is a UVB blocker. Dibenzoylmethane (avobenzone; Parsol 1789) is a UVA/UVB blocker. Red veterinary petrolatum is a UVA blocker.
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How long after isotretinoin therapy can one safely begin trying to conceive?
1 Immediately
2 Two weeks
3 One month
4 One year
5 Three years
A woman should wait one month before trying to conceive after taking isotretinoin to prevent birth defects. After taking acitretin a woman should wait three years before trying to conceive.
Q/Q(M)-477507 Report a Problem
Which of the following medications is most likely to interefere with the efficacy of oral contraceptives?
1 Rifampin
2 Tetracycline
3 Doxycycline
4 Trimethoprim-sulfamethaxasole
5 Amoxicillin
Rifampin has been shown to decrease the efficacy of oral contraceptives. It is an inducer of cytochrome p450 which increases the metabolism of hormones thereby decreasing the efficacy of oral contraceptives. There is no clear decrease in oral contraceptive efficacy with concomitant use of ampicillin, ciprofloxacin, clarithromycin, doxycyline, metronidzole, ofloxacin, or tetracycline.
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Which of the following statements is NOT true regarding the categories for safety of drug use in pregnancy?
1 Drugs are category A if controlled studies in humans show no risk to the fetus
2 Drugs are category B if controlled human studies show no risk to the fetus but may show risk to animals, or if no risk has been shown in animal studies but no human studies have been conducted
3 Drugs are category C if risk to the human fetus has been demonstrated, but animal studies are equivocal
4 Drugs are category D if controlled studies show risk to human fetus, but in some instances benefits may outweigh risks
5 Category X drugs are contraindicated in pregnancy
Drugs are category C if risk to the human fetus cannot be ruled out, studies are lacking, or animal studies are equivocal. Drugs for which risk to the human fetus has been demonstrated are pregnancy category D.
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Which of the following has been associated with a lichenoid drug eruption?
1 Sulfasalazine
2 Hydrochlorothiazide
3 Acetaminophen
4 Erythromycin
5 Nicotinamide
Lichen-planus-like (lichenoid) drug eruptions have been reported with: antimalarials, ?-blockers, captopril, gold, penicillamine, HCTZ, NSAIDs. Lichenoid drug reactions are often photodistributed.
Q/Q(M)-474329 Report a Problem
All of the following statements are true regarding cyclosporin A EXCEPT:
1 Adverse effects include hypertrichosis and gingival hyperplasia
2 The most common eletrolyte abnormalities are hypokalemia and hypermagnesemia
3 Forms a complex with cyclophilin, blocking its ability to activate calcineurin, thus preventing calcineurin from de-phosphorylation NFAT-1
4 Metabolized by the hepatic cytochrome P-450 3A4 enzyme system
5 NSAIDs can potentiate renal toxicity when combined with cyclosporine
The most common electrolyte abnormalities associated with cyclosporin A are hyperkalemia, hyperuricemia, and hypomagnesemia.
Q/Q(M)-475611 Report a Problem
A patient taking daily prednisone is advised to switch to alternate day dosing to decrease the risk of:
1 Glaucoma
2 Aseptic bone necrosis
3 Cataracts
4 Adrenal crisis
5 Osteoporosis
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.
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The agent of choice used to acutely lower methemoglobin levels in patients taking dapsone is:
1 Cimetidine
2 Oral methylene blue
3 Homocysteine
4 Vitamin E
5 Glucose-6-phosphatase
Cimetidine and vitamin E have both been known to provide prophylaxis against methemoglobin formation. G6PD-deficient individuals are at greater risk of hematologic toxicity from dapsone.
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Ketoconazole and itraconazole are potent inhibitors of which one of the following cytochrome p450 isozymes?
1 2C9
2 2D6
3 3A4
4 1A2
5 2C18
Ketoconazole has been shown to be the strongest inhibitor of cytochrome p450 (CYP) 3A4. Itraconazole is an inhibitor of CYP 3A4, whereas fluconazole inhibites CYP 2C9 significantly more than minimal inhibitory role of CYP 3A4. Terbinafine inhibits CYP 2D6.
Q/Q(M)-478602 Report a Problem
A 15 year old boy presents with a 4 month history of pigmented bands on several fingernails and toenails. The most like etiology is:
1 Peutz-Jeghers syndrome
2 Chloroquine therapy
3 Minocycline therapy
4 Nevomelanocytic nevi
5 Acral lentiginous melanoma
Melanonychia occurring simultaneously on several nails is most likely to be due to minocycline therapy. Blue-black pigmentation may be present in nails, skin, scars and sclerae.
Q/Q(M)-477321 Report a Problem
Which drug has been associated with an increased incidence of serum sickness in children?
1 Rifampin
2 Clarithromycin
3 Ciprofloxacin
4 Clindamycin
5 Cefaclor
Cefaclor has been associated with an increased incidence of serum sickness in children; the other drugs have not.
Q/Q(M)-475196 Report a Problem
Which of the following bones will develop the most dramatic changes in density following oral glucocorticoids?
1 Femur of 72 year old female
2 Femur of 72 year old male
3 Vertebrae of 22 year old male
4 Vertebrae of 22 year old female
5 Vertebrae of 72 year old female
Although post menopausal women are at greatest risk for fractures from steroid therapy (they have the weakest bones to begin with), it is young men who have the most dramatic decrease in bone density. Young men have the highest bone density on average and therefore will show the greatest change with steroid therapy. Trabecular bone (ribs, vertebrae) are more affected than cortical bones (long bones) due to higher metabolic rate of the former. Also, most demineralization occurs during the first 6-12 months of therapy. This highlights the fact that even young men who are not traditionaly at risk for fractures, need prophylaxis for osteroperosis while on systemic steroids.
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Which of the following pairings of antifungal agents and their mechanisms of action is NOT correct?
1 Terbinafine: Inhibits squalene epoxidase
2 Itraconazole: Inhibits 14-alpha-demethylase
3 Griseofulvin: Disrupts microtubule mitotic spindle formation
4 Ketoconazole: Blocks conversion of lanosterol to ergosterol
5 Fluconazole: Inhibits squalene epoxidase
Terbinafine inhibits squalene epoxidase and blocks the biosynthesis of ergosterol, a sterol essential to the integrity of fungal cell membranes. Itraconazole inhibits 14-alpha-demethylase, blocking lanosterol conversion to ergosterol. Griseofulvin disrupts microtubule mitotic spindle formation causing metaphase arrest. Ketoconazole has a mechanism of action similar to itraconazole. Fluconazole also inhibits 14-alpha-demethylase, not squalene epoxidase.
Q/Q(M)-475206 Report a Problem
The antihistamine with strong H1 and H2 blockade is:
1 Chlorpheniramine
2 Cetirizine
3 Cimetidine
4 Cyproheptadine
5 Doxepin
Doxepin, a tricyclic antidepressant, has H1 and H2 antihistamine activity.
Q/Q(M)-474479 Report a Problem
Which of the following drugs is correctly matched to its target enzymes?
1 Tacrolimus-Thymidine kinase
2 Methotrexate-Inosine monophosphate dehydrogenase
3 Mycophenolate Mofetil-Phospholipase A2
4 Acyclovir-DNA polymerase
5 Terbinafine-Cytochrome p450
Drug/Specific enzyme inhibited Tacrolimus - Calcineurin Methotrexate - Dihydrofolate reductase Mycophenolate mofetil - Inosine monophosphate dyhydogenase Acyclovir - DNA Polymerase Terbinafine - Squalene epoxidase
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