Assessing the safety of topical minoxidil through disproportionality analysis of FAERS reports

Topical minoxidil, approved by the FDA in the 1980s, has been widely used to manage androgenetic alopecia. While effective, several adverse events (AEs) related to its use, especially those not well-documented on product labels, remain a concern.

This study aimed to evaluate the safety of topical minoxidil by analyzing AEs reported in the FDA Adverse Event Reporting System (FAERS) from 2004 to 2024, focusing on identifying potential risk signals not highlighted on current product labels.

Adverse event reports (AERs) from FAERS, where topical minoxidil was identified as the primary suspect, were analyzed. Disproportionality analysis methods, Reporting Odds Ratio (ROR), Proportional Reporting Ratio (PRR), Bayesian Confidence Propagation Neural Network (BCPNN), and Multi-Item Gamma Poisson Shrinker (MGPS), were used to assess the relationship between minoxidil and reported AEs.

Among 45,130 reports, most were from males (50.88%) and showed a significant increase in incidents since 2015. Newly identified AEs, such as application site acne and cysts, were observed. These AEs are not well represented on product labels.

The study identified previously unreported AEs linked to topical minoxidil, underscoring the need for updated patient information and regulatory reassessment to enhance safety and inform clinical practices.