Propecia also known as Finasteride is used by patients to prevent the enlargement of the prostate gland and some men use it to help with male pattern baldness. Problems obtaining an erection and also a reduction in the production of semen have been seen in about two percent of men who have used Propecia. Merck, who manufactures Propecia, has warned that men using Propecia can experience a reduction in the amount of semen that is released while ha...
