Background: Finasteride, a 5α-reductase inhibitor (5αRI) for benign prostatic hyperplasia and androgenetic alopecia (AGA), has been linked to persistent multisystemic symptoms—most often sexual dysfunction—that may appear during or after use and persist post-discontinuation. Case Description: A 26-year-old man treated with finasteride 1 mg for AGA discontinued therapy after 6 months due to genital hypoesthesia and reduced ejaculatory potency. Other physical, psychological, and relational causes were excluded. Symptoms persisted 19 months after cessation. Discussion: Reports of persistent adverse effects (≥3 months) have increased, without correlation to dose, age, or treatment duration. Prevalence, mechanisms, and symptom duration are unclear; cases exceeding 40 months are documented. Though mainly sexual in nature, symptoms can include neurological, hormonal, and psychiatric issues, with no proven treatment. Conclusion: Post-finasteride syndrome (PFS), though rare, significantly impacts quality of life, with unclear etiology and no definitive treatment. Risk-benefit assessment and informed patient consent are essential before prescription.
Sofia Mendes Cunha (Mon,) studied this question.