Emerging and traditional 5-α reductase inhibitors and androgen receptor antagonists for male androgenetic alopecia

ABSTRACT

Introduction

Androgenetic alopecia (AGA) is the most prevalent cause of male hair loss, often requiring medical and/or surgical intervention. The US FDA has approved topical minoxidil and oral finasteride for male AGA treatment. However, some AGA patients fail to respond satisfactorily to these FDA-approved treatments and/or may experience side effects, based on their individual profiles. To mitigate the shortcomings of these treatments, researchers are now exploring alternative treatments such as newer 5-α reductase inhibitors (5-ARIs) and androgen receptor antagonists (ARAs).

Areas covered

This article reviews the safety and effectiveness of well-known 5-α reductase inhibitors (5-ARIs) like finasteride and dutasteride, as well as the newer 5-ARIs, emerging androgen receptor antagonists (ARAs), and natural products such as saw palmetto and pumpkin seed oil in the treatment of male AGA.

Expert opinion

Although several newer 5-ARIs, ARAs, and natural products have exhibited promise in clinical trials, additional research is essential to confirm their safety and efficacy in treating male AGA. Until additional evidence is available for these agents, the preferred treatment choices for male AGA are the FDA-approved treatments, topical minoxidil, and oral finasteride.

KEYWORDS:

• Male AGA
• alopecia
• 5-α reductase inhibitors
• androgen receptor inhibitors
• male pattern baldness

Article highlights

• Topical minoxidil and oral finasteride are the only FDA-approved treatments for male androgenetic alopecia (AGA).

• The distribution of oral finasteride and oral dutasteride is minimal in the semen; therefore, male users of these two drugs pose little risk to their female partner’s potential pregnancy, although further research is needed.

• Fathering children may be challenging for men with preexisting fertility problems who take finasteride or dutasteride to treat AGA.

• Clinical trials suggest that oral dutasteride 0.5 mg/day may be more effective than oral finasteride 1 mg/day for treating male AGA.

• Men with androgenetic alopecia (AGA) tend to have an elevated dihydrotestosterone (DHT) level. Blocking the production or the effect of DHT may slow down the progression of AGA and improve hair growth.

• In clinical trials, topical preparations of 5-α reductase inhibitors (e.g. alfatradiol, episteride), androgen receptor inhibitors (e.g. spironolactone, bicalutamide, clascoterone, pyrilutamide), natural products (e.g. saw palmetto, pumpkin seed oil) have shown promise for treating male AGA.

Declaration of interests

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.