Finasteride - A review of its use in male pattern hair loss

The 5 alpha-reductase inhibitor finasteride blocks the conversion of testos terone to dihydrotestosterone (DHT). the androgen responsible for male patt ern hair loss (androgenetic alopecia) in genetically predisposed men. Results of phase III clinical studies in 1879 men have shown that oral fina steride 1 mg/day promotes hair growth and prevents further hair Loss in a s ignificant proportion of men with male pattern hair loss. Evidence suggests that the improvement in hair count reported after 1 year is maintained dur ing 2 years' treatment. In men with vertex hair loss, global photographs sh owed improvement in hair growth in 48% Of finasteride recipients at 1 year and in 66% at 2 years compared with 7% of placebo recipients at each time p oint, Furthermore, hair counts in these men showed that 83% of finasteride versus 28% of placebo recipients had no further hair loss compared with bas eline after 2 years. The clinical efficacy of oral finasteride has not yet been compared with th at of topical minoxidil, the only other drug used clinically in patients wi th male pattern hair loss. Therapeutic dosages of finasteride are generally well tolerated. In phase I II studies, 7.7% of patients receiving finasteride 1 mg/day compared with 7 .0% of those receiving placebo reported treatment-related adverse events. T he overall incidence of sexual function disorders, comprising decreased lib ido, ejaculation disorder and erectile dysfunction, was significantly great er in finasteride than placebo recipients (3.23 vs 2.1%). All sexual advers e events were reversed on discontinuation of therapy and many resolved in p atients who continued therapy. No other drug-related events were reported w ith an incidence greater than or equal to 1% in patients receiving finaster ide. Most events were of mild to moderate severity. Oral finasteride is contraindicated in pregnant women because of the risk o f hypospadias in male fetuses. Conclusions: Oral finasteride promotes scalp hair growth and prevents furth er hair loss in a significant proportion of men with male pattern hair loss . With its generally good tolerability profile, finasteride is a new approa ch to the management of this condition, for which treatment options are few . Its role relative to topical minoxidil has yet to be determined.