Gender Differences in Adverse Effects and Dosing Practices of Low-Dose Oral Minoxidil for Androgenetic Alopecia: A Retrospective Analysis of 310 Patients.

INTRODUCTION

Off-label low-dose oral minoxidil (LDOM) is used for androgenetic alopecia (AGA) treatment, with limited safety data. We investigated LDOM adverse effects (AEs) in AGA patients.

METHODS

AGA patients taking LDOM were identified (January 1, 2010-December 3, 2022). AEs and management were recorded from follow-up and emergency room visits. Fisher's exact test, logistic regression, and Benjamini-Hochberg procedure assessed significance and adjusted for multiple comparisons.

RESULTS

Three hundred ten AGA patients were analyzed with mean age 47.5 years and 53.2% females. The average LDOM dose was lower for females vs. males. AEs were observed in 14.9% of patients, with dizziness/lightheadedness, hypertrichosis, and extremity edema being most common. Higher doses were associated with increased likelihood of dizziness/lightheadedness. Females had higher overall incidence of AEs; however, gender differences did not persist after subgroup analysis. Among patients experiencing AEs, 11.1% adjusted their dosage and 28.9% discontinued treatment.

CONCLUSION

A higher LDOM dose increased risk of dizziness/lightheadedness in both genders, with females more likely to experience any AE. Patients are often started at inappropriately high doses, causing AE-induced regimen changes. Therefore, we recommend a cautious approach when prescribing LDOM, starting with lower doses and gradually increasing as tolerated, and counseling female patients regarding their higher risk of AEs.