A New Era of 5α-Reductase Inhibitors for Androgenetic Alopecia

The article discusses a new era of 5α-reductase inhibitors for androgenetic alopecia (AGA). Oral finasteride and topical minoxidil have been used as therapeutic drugs for AGA, but a new oral drug dutasteride has been reported to be efficient for AGA in a large-scale randomized controlled trial. Dutasteride suppresses both type I and II 5α-reductases while finasteride significantly suppresses only type II. Therefore, dutasteride is referred to as a “dual inhibitor”. In the randomized controlled trial, dutasteride significantly increased hair count and width and hair photographic assessment compared with finasteride. However, it is still controversial whether there is a significant difference in clinical efficiency by dutasteride and finasteride. The recent Korean study pointed out that sexual dysfunction occurred in 17.1% AGA patients treated with dutasteride while it was transient. Therefore, if dutasteride becomes available for AGA in the future, it is important to use it carefully, especially for sexual side effects.