Dutasteride For Treating Male Hair Loss
Dutasteride is occasionally used off-label for the treatment of hair loss in men who have not responded to finasteride. It is only FDA approved for the treatment of benign prostatic hypertrophy (trade name Avodart®). It works by inhibiting both type I and type II 5-alpha reductase enzyme. It is approximately 3x as potent as finasteride at inhibiting the type II enzyme (involved in DHT production) and can decrease serum DHT levels by slightly more than finasteride. However it has a significantly longer half-life than finasteride so any side effects may last for 8 or more weeks. For this reason it is only a good considered for men who have already had their families and who have not seen an adequate response to finasteride. Like finasteride, it is teratogenic in women of childbearing age. Men who are taking it should not donate blood for 6 months after their last dose to avoid inadvertent administration to a pregnant female.