Should I worry about finasteride side effect reports?
Q. I have read several news reports that claim finasteride, which I take for my prostate problem, can cause permanent impotence. Should I be concerned?
A. Finasteride (sold as Proscar and generic brands) is prescribed for symptoms of an enlarged prostate; it's also used at a lower strength (under the name Propecia) for male pattern baldness. Finasteride blocks the metabolism of testosterone. It can prevent hair loss and decrease prostate enlargement, but not surprisingly, it can also suppress sexual function. However, the side effects of a medication usually go away when you stop taking it.
In April 2012, the FDA issued a warning on finasteride. It stated that sexual side effects could persist even after stopping the medication. Those side effects include decreased sex drive and ejaculation problems. The warning was based on about 100 reports the FDA received over nearly 20 years. This is not proof that finasteride was to blame, since a variety of medical conditions and prescription drugs could explain the sexual symptoms the men reported while taking finasteride.