The prescription drug Propecia was originally developed to treat benign prostate conditions. Then its manufacturer Merck discovered that it has a side effect that is even more desirable - stimulating hair growth. So it has evolved into a very lucrative anti-baldness drug.
However, recently another side effect for Propecia has been reported, and it is not a welcome one - ED.
It is ironic that a drug that might help a guy look more attractive to women might also prevent him from consummating his romantic conquest.