Drugs and alopecia

Abstract

Drugs are a relatively common cause of diffuse, nonscarring hair loss. They may interfere with the normal hair cycle, either by an abrupt cessation of the mitotic activity of matrix cells, causing anagen effluvium, or by an interruption of the anagen and a premature passage to the telogen phase, originating telogen effluvium. It is essential to obtain a complete history, including previous diseases and medications, focusing on the past 3 months, in order to rule out possible drug-induced alopecia. This review encompasses the most frequently involved drugs, including mechanisms of action and clinical characteristics of drug-induced alopecia. The correct recognition of drug-induced alopecia is essential since the main approach is to stop the offending agent, whenever it is possible.