Erythema annulare centrifugum secondary to treatment with finasteride.

Cutaneous eruptions are among the most common adverse reactions to drugs. We report a novel case of erythema annulare centrifugum occurring after the administration of finasteride for androgenetic alopecia. The eruption resolved once the drug was discontinued and reappeared with reintroduction of finasteride. This case may encourage reporting of similar cases and further study of finasteride hypersensitivity.