Comparison of oral minoxidil, finasteride, and dutasteride for treating androgenetic alopecia

Abstract

Background

Androgenetic alopecia (AGA) is the most common cause of hair loss, often challenging to treat. While oral finasteride (1 mg/d) is an FDA-approved treatment for male AGA, oral minoxidil and oral dutasteride are not approved yet. However, clinicians have been increasingly using these two drugs off-label for hair loss. Recently, Japan and South Korea have approved oral dutasteride (0.5 mg/d) for male AGA.

Efficacy and safety

A probable efficacy ranking, in decreasing order, is – dutasteride 0.5 mg/d, finasteride 5 mg/d, minoxidil 5 mg/d, finasteride 1 mg/d, followed by minoxidil 0.25 mg/d. Oral minoxidil predominantly causes hypertrichosis and cardiovascular system (CVS) symptoms/signs in a dose-dependent manner, whereas oral finasteride and dutasteride are associated with sexual dysfunction and neuropsychiatric side effects.

Pharmacokinetics and pharmacodynamics

The average plasma half-lives of minoxidil, finasteride, and dutasteride are ∼4 h, ∼4.5 h, and ∼5 weeks, respectively. Minoxidil acts through multiple pathways to promote hair growth. It has been shown as a vasodilator, an anti-inflammatory agent, a Wnt/β-catenin signaling inducer, and an antiandrogen. Finasteride inhibits 5α-reductase (5AR) type II isoenzyme, while dutasteride inhibits both type I and type II. Thus, dutasteride suppresses DHT levels more than finasteride in the serum and scalp.

Keywords:

• Hair loss
• androgenetic alopecia
• male pattern hair loss
• female pattern hair loss
• oral minoxidil
• oral finasteride
• oral dutasteride

Ethics approval

Not applicable. The authors declare that human ethics approval was not required for this article.

Author contributions

Conception of the manuscript by AKG. The work was drafted by MT and GW, and substantively revised by AKG, MT, and GW.

Consent to participate: Not applicable; Consent for publication: Not applicable; Availability of data and material: Not applicable; Code availability: Not applicable.

Disclosure statement

AKG, MT, and GW have no conflict of interest to declare.