Is the Safety of Finasteride Correlated With Its Route of Administration: Topical Versus Oral? A Pharmacovigilance Study With Data From the United States Food and Drug Administration Adverse Event Reporting System

This pharmacovigilance study analyzed FDA Adverse Event Reporting System data to compare the safety of topical versus oral finasteride, focusing on post-finasteride syndrome (PFS)-like adverse events (AEs). The study found that signals for PFS-like AEs were less frequent with topical finasteride compared to oral finasteride across two time periods, 2006–2011 and 2019–2024. No signals were detected for topical dutasteride, likely due to its limited use. The study highlights that many reported AEs, such as erectile dysfunction and depression, may be influenced by factors like age, stress, or comorbidities. The findings suggest that while topical finasteride may pose a lower risk of PFS-like AEs, more robust evidence is needed to fully understand its safety profile, considering the potential influence of confounding factors and the lack of comprehensive data in most reports.