Dermatological pharmacology

Question 1

What class of drugs are Isotretinoin, 
Acitretin?

Answer 1

Retinoids

Stimulate epithelial cell turnover; also anti-inflammatory

Teratogenic effects (washes out in three weeks)

Good as adjunct to other therapies

Question 2

What is the MOA of a retinoid for dermatologic use?

Answer 2

Stimulate epithelial cell turnover; also anti-inflammatory

Question 3

What would you use isotretinoin for?

Acitretin?

Answer 3

isotretinoin for acne

acitretin for psoriasis

both have “retin” in the name.

Question 4

MOA for UV light therapy ?

Answer 4

different classes: UVA, UVB, UVC

Immunosuppression of T-cells via type I or type II reactions –> mono- or bifunctional adducts in DNA

Question 5

Uses for UV light therapy? Side effects?

Answer 5

Inflammatory conditions: atopic dermatitis, CTCL, lichen planus, psoriasis (not useful for non-inflammatory conditions)

Skin cancer, thinning/leathering of skin

Usually used with psoralens (photosensitizing agents that increase efficacy); phenothiazines, thiazides, sulfonamides, NSAIDs, tetracycline, benzodiazapenes also sensitize skin to light therapy

Question 6

What is a biologic?

Answer 6

Blocks TNF-a

used for Inflammatory conditions, arthritis

side effects: Few (may unmask neurologic disease, latent infections (must do PPDs), malignancies)

Expensive

Question 7

MOA for methotrexate? Uses? Side effects?

Answer 7

Folate analouge; inhibits dihydroxyfolate reductase

used for Inflammatory conditions (psoriasis), conditions needing immunosuppression

Side effects: Hepatotoxicity (develops slowly, can give up to 4.5 g over life); pulmonary toxicity (develops quickly); leukopenia; rarely, renal toxicity. Nausea, vomiting

Misc: PO, IM (1/week); any drug increasing unbound protein may cause methotrexate toxicity (sulfa, salicylates, TCN, phenytoin)

Question 8

Cyclosporin - class, uses, side effects?

Answer 8

Immunosuppressant

Inflammatory conditions (psoriasis)

Raises blood pressure, damages kidneys if used long-term

Question 9

Hydrocortisone - class, uses, side effects?

Answer 9

Steroid

Uses: Dermatitis, psoriasis

Side effects: Atrophy/thinning of skin (collagen), stretch marks, talangiectasias, acne, cataract or glaucoma if applied near eye. Systemically, affects hypothalamic-pituitary-adrenal axis –> growth retardation

misc: Seven classes, w/class I being the strongest and class VII being the weakest; side effects may be permanent

Question 10

Monophasic dermatologic vehicles include:

Answer 10

Powders;
Greases;
Liquids

Question 11

Biphasic dermatologic vehicles include:

Answer 11

Lotions: liquid + powder
Paste: Ointment + powder
Creams: Grease + liquid

Question 12

Long-term application of corticosteroids near the eye can cause:

Answer 12

glaucoma;

cataracts

Question 13

What UV rays are associated with skin cancer?

Answer 13

UVA - penetrates more deeply, associated with aging and cancers

Question 14

Phototherapy can be useful in the short-term to treat:

Answer 14

Psoriasis;
Atopic dermatitis;
CTCL;
lichen planus
**common theme is inflammatory conditions**

Question 15

What is a good medication to treat extensive psoriasis in patients with no joint involvement?

Answer 15

Methotrexate

One bad side effect is pulmonary toxicity (within 2 weeks of starting drug)

Question 16

Should retinoids be given during pregnancy?

Answer 16

No

can result in profound growth abnormalities

Question 17

TNF-alpha is a key mediator of inflammation in what dermatologic condition?

Answer 17

Psoriatic arthritis

upregulation of cytokines

Question 18

What are the side effects of biologics?

Answer 18

Infections (rare);
Malignancies;
Site reactions where administered;
unmasking of neurologic disease ie MS

use for psoriasis with joint involvement

Question 19

How long should women wait before becoming pregnant after being given Soriatane (acetretin)?

Answer 19

Soriatane is a retinoid, which can be reverse-metabolized to etretinate, which has an extremely long half-life. Wait 3 years before becoming pregnant!