Efficacy and safety of oral finasteride <i>versus</i> dutasteride in moderate-to-severe androgenetic alopecia in males based on trichoscopic and laboratory findings: a clinical comparison in Iran

Background Androgenetic alopecia (AGA) is the most common type of hair loss in men. Finasteride and dutasteride are oral 5-alpha-reductase inhibitors. This study compared their efficacy and safety in Iranian men with moderate to severe AGA.Methods This randomized single-blind clinical trial included 46 men aged 20–50 years. Patients received finasteride 1 mg daily or dutasteride 0.5 mg daily for 24 weeks. Hair density and thickness were measured by trichoscopy and photographs. Satisfaction was recorded with a visual analog scale (VAS). Adverse effects were documented.Results Both groups improved in hair growth after 24 weeks with no significant difference. Serum PSA fell in the dutasteride group from 0.63 ± 0.18 to 0.42 ± 0.22 (p < 0.001). No significant change appeared in the finasteride group. Dutasteride produced greater PSA reduction than finasteride (B = 0.17, p < 0.01). Age had no effect on PSA (p = 0.58). VAS scores showed no difference. Safety profiles were similar. Sexual side effects were most common, with erectile dysfunction more frequent in the finasteride group. No serious events occurred.Conclusion Finasteride and dutasteride improved hair density with similar safety. Dutasteride caused stronger PSA reduction, suggesting more potent 5-alpha-reductase inhibition.