HY lecture notes:
The majority of acne is treated as follows:
- Topical retinoids first (i.e., topical tretinoin; NOT oral isotretinoin) ; cause photosensitivity (rash); also used for photoaging; mechanism is decreasing sebum production; topical tretinoin (not oral isotretinoin) is not a teratogen and does not have any effect on pregnancy or male sperm.
- Benzoyl peroxide used second; often coadministered with topic retinoids; mechanism is the killing of bacteria.
- Topical clindamycin
- Oral tetracycline; causes photosensitivity (blistering)
- Oral isotretinoin; must do beta-hCG in women; recommend barrier contraception even if on OCP; can cause elevations in LFTs; can cause dyslipidemia; main complaint is dry skin + peeling; takes several weeks to really start working but ultra-effective according to most patients; can be commenced earlier in patients with severe nodulocystic acne; works by diffusely shutting of sebum production.
There is an NBME question floating around where they say they say a girl is starting on OCPs at the same time as isotretinoin, and then they ask what else you should do, and the answer is “recommend barrier contraception.” Students get this wrong because they say, “Wait, I don’t get it, why two methods?” We can debate it all we want, but it’s still on the NBME.
Students may ask, “USMLE is actually that pedantic about acne management?” My answer: 2CK will assume you know #1+2 are used first and that #5 is last resort for most patients, and that #1 and #4 cause photosensitivity; Step 1 wants you to know mechanisms of the drugs in terms of how they actually treat the acne (which I’ve written above).
