Effect of finasteride 5 mg (Proscar) on acne and alopecia in female patients with normal serum levels of free testosterone

Background. In some women with acne or alopecia who have normal serum levels of free testosterone, no clinical improvement can be reached by the classical treatment with antiandrogens, isotretinoids or corticosteroids. Our hypothesis is that some of these women have an excessive activity of the enzyme 5α-reductase. Objective. To evaluate the subjective benefit of the treatment with finasteride (5 mg day) in women with normal serum levels of free testosterone suffering from acne or alopecia. Design. This was a retrospective study evaluating a questionnaire filled out by 12 patients, six of whom had acne and six of whom had alopecia. Results. Nine of the 12 patients benefited from the treatment, their symptoms decreased significantly and they felt better psychologically than before the administration of finasteride. The other three patients did not benefit at all from finasteride and reported no change in the extent of the acne alopecia. Treatment was generally well tolerated, only a few adverse effects were noted. Conclusions. Nine of the 12 patients benefited from the treatment. This supports our hypothesis of an excessive activity of 5α-reductase enzyme in peripheral tissue in these patients. The fact that three of the patients did not realize any change in their symptom severity implies that there must also be other pathways in the genesis of acne and alopecia in women with normal levels of free testosterone. Further evaluation is needed to elucidate more precise indications for the administration of finasteride in women with acne and alopecia.