Pharmacological Role and Clinical Applications of 5α-Reductase Inhibitors-Review Article for Pharmacists and Healthcare Professionals

Saud Alhabeeb; Abdullah Abdulaziz Almetrek; Marwan Ibraheem Al-Amri; Ali Abdulrahman Ali Alajlan; Fahad Abdullah Saleh Alfehaid; ‪Mohanad Khaled Ibrahim Alsaudi; Abdullah Abdulaziz Abdulrahman Alsheeb

doi:10.64483/jmph-40

Authors

Saud Alhabeeb Kingdom of Saudi Arabia, Red Crescent Authority
Abdullah Abdulaziz Almetrek Kingdom of Saudi Arabia, Red Crescent Authority
Marwan Ibraheem Al-Amri Kingdom of Saudi Arabia, Red Crescent Authority.
Ali Abdulrahman Ali Alajlan Kingdom of Saudi Arabia, Qassim University.
Fahad Abdullah Saleh Alfehaid Kingdom of Saudi Arabia, Qassim University.
‪Mohanad Khaled Ibrahim Alsaudi Kingdom of Saudi Arabia, Qassim University.
Abdullah Abdulaziz Abdulrahman Alsheeb Kingdom of Saudi Arabia, Qassim University.

DOI:

https://doi.org/10.64483/jmph-40

Keywords:

5α-reductase inhibitors, finasteride, dutasteride, BPH, androgenic alopecia, DHT inhibition

Abstract

Background: 5α-reductase inhibitors (5-ARIs), including finasteride and dutasteride, are FDA-approved for treating benign prostatic hyperplasia (BPH) and androgenic alopecia. These agents inhibit the conversion of testosterone to dihydrotestosterone (DHT), reducing prostate volume in BPH and slowing hair loss in androgenic alopecia. Despite their efficacy, concerns regarding adverse effects, such as sexual dysfunction and post-finasteride syndrome, necessitate careful patient selection and monitoring.

Aim: This review evaluates the pharmacological mechanisms, clinical applications, and safety profiles of 5-ARIs, providing evidence-based guidance for pharmacists and healthcare professionals.

Methods: A comprehensive literature review was conducted, analyzing clinical trials, meta-analyses, and guidelines on 5-ARI use in BPH, androgenic alopecia, and off-label indications.

Results: 5-ARIs significantly improve urinary symptoms in BPH (reducing prostate volume by ~25%) and stabilize hair loss in 88% of alopecia patients. Dutasteride offers broader DHT suppression but clinical efficacy similar to finasteride. Adverse effects include sexual dysfunction (e.g., erectile dysfunction, reduced libido) and gynecomastia. Off-label uses (e.g., hirsutism, bladder cancer prevention) show promise but require further validation.

Conclusion: 5-ARIs are cornerstone therapies for BPH and androgenic alopecia, though their use demands individualized risk-benefit assessment. Multidisciplinary collaboration ensures optimal outcomes.

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