Dutasteride
Off-label hair-loss drug. Blocks DHT more completely than finasteride.
FDA-approved for benign prostatic hyperplasia at 0.5mg/day, used off-label for male-pattern hair loss. Blocks both isoforms of 5-alpha reductase (finasteride blocks only one). Suppresses DHT ~90% vs ~70% for finasteride. Stronger effect but smaller evidence base; consider after finasteride trial.