I have been on 1/5 proscar for 2 months now and it has actually caused a massive increase in my sex drive. Is this because of the medication!? I have only read about it causing a decrease in libido. However it is a side affect I think I can live with :)
Finasteride will often increase the testosterone levels and I have heard reports of an increased sex drive. Few men have complained about it, but when it happens to an older married man, it is oftentimes the wife that will do the complaining.