As the subject header says, T Nation has an article about different hairloss options. I was pleased to read their entry on Finasteride:
Finasteride
Finasteride is an extremely popular medication used by thousands of men to treat symptoms of an enlarging prostate. However, it’s also exceptionally good at treating symptoms of hair loss; so effective in fact that it’s the only other FDA approved treatment for hair loss besides Minoxidil.
Frequently appearing as the brands Proscar or Propecia, finasteride is a 5-alpha reductase inhibitor, capable of preventing the conversion of testosterone to its metabolite DHT.
However, Finasteride is often not kind. It’s notorious for its range of negative sexual side effects, including inability to maintain or achieve an erection, as well as causing libido and ejaculation issues. In the past, Finasteride was deemed ineffective when used topically, but a recent study determined that a topical form was effective if combined with Minoxidil for maintenance (after an initial two years of oral treatment).
Finasteride is currently being studied for causing a phenomenon known as “post finasteride syndrome” or PFS. PFS is attributed to changes in neuro-chemical levels following cessation of its use, resulting in suicidal idealation and depression, along with total loss of sexual function. It’s likely that the results of the study, along with mounting pressure from consumers, could result in its withdrawal from the market completely.