What Do We Know About 5-Alpha Reductase Inhibitors?
January 2018
in “
Surgical and Cosmetic Dermatology
”
Studysummary This review provides an in-depth examination of the efficacy and safety of finasteride and dutasteride, commonly used for treating benign prostatic hyperplasia and male androgenetic alopecia.
Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer
Five years ago, a study at the Instituto de Dermatologia Integral in Madrid, Spain, reviewed the efficacy and safety of 5-alpha reductase inhibitors, finasteride and dutasteride, in treating benign prostatic hyperplasia and androgenic alopecia. Finasteride, approved by the FDA in 1991 and 1997, reduces dihydrotestosterone (DHT) levels by 70% at a 5mg/day dose. Dutasteride, approved by the FDA in 2002, reduces DHT levels by over 90% at a 0.5mg/day dose. Both drugs were classified as Level I evidence in treating male androgenetic alopecia, but were associated with a low incidence of reversible sexual side effects. In women, finasteride was classified as Level III evidence, and a 2017 review found that 1mg/day finasteride did not yield better outcomes than a placebo. The study also explored alternative uses of these drugs, such as topical finasteride and capillary mesotherapy with dutasteride.
