Widespread Skin Hypopigmentation Caused by Finasteride When Used for Female Hirsutism

A 39-year-old woman with hirsutism and hyperandrogenism was treated with finasteride, which improved her symptoms but led to widespread skin hypopigmentation. Her testosterone levels normalized after stopping exogenous supplements, but the skin lightening persisted despite sun-bed use. The patient, of mixed Afro-Caribbean and Caucasian descent, experienced significant anxiety due to the skin changes. Finasteride was discontinued, and dermatology consultation was sought to assess melanocyte activity. Laboratory findings suggest finasteride may decrease tyrosinase activity, impacting melanogenesis. This potential side effect should be discussed with patients before starting treatment.