Why doesn't some acne medication work on me?

Keep trying: Benzoyl peroxide is the only one you can buy yourself that does any good. Your physician may have tried a retinoic acid derivative and topical clindamycin. A good next step is systemic tetracycline 500 2x/day. The last is accutane, which is unplesant & has risks but will do the job. Or you may not actually have acne but one of its mimics. Consider a specialist visit.