Background: Androgenetic alopecia (AGA) is a chronic, androgen-dependent disorder driven by dihydrotestosterone (DHT)-mediated follicular miniaturization. Oral finasteride is the established first-line therapy, while dutasteride, which blocks both type I and type II 5-alpha-reductase isoenzymes, is increasingly used off-label. Head-to-head, long-duration data from Indian patients remain scarce.
Objective: To compare the efficacy and safety of oral finasteride (1 mg/day) and oral dutasteride (0.5 mg/day) in men with AGA at a tertiary care centre in Uttar Pradesh.
Methods: In this prospective interventional comparative study, 120 men aged 18–40 years with Hamilton–Norwood grade II–V AGA were allocated to finasteride (n=60) or dutasteride (n=60) and followed for 18 months. Efficacy was assessed by phototrichogram, global photography and patient self-assessment at 6-month intervals; safety was assessed through clinical monitoring and 3-monthly laboratory investigations.
Results: Baseline demographic and disease-severity parameters were comparable between groups (p>0.05 for all). Terminal hair density increased from 160.9 to 175.6 hairs/cm² with finasteride (+9.1%) and from 161.4 to 188.9 hairs/cm² with dutasteride (+17.0%; p<0.001 at 18 months). Vellus hair count declined by 10.8% with finasteride versus 20.3% with dutasteride (p=0.02). Marked-to-moderate improvement on global photography was seen in 56.7% versus 73.3% of patients respectively (p<0.01), and overall marked improvement occurred in 56.7% versus 76.7% (p<0.001). Sexual adverse effects were numerically higher with dutasteride (23.3% vs. 16.7% any adverse effect) but the difference was not statistically significant, and no patient discontinued therapy.
Conclusion: Both agents were effective and well tolerated, but dutasteride produced significantly greater and faster improvement in hair density with a comparable safety profile, supporting its preferential use in moderate-to-severe disease or in patients responding inadequately to finasteride.