Caverject is the first prescription drug approved for impotence. A hormone-like element, Alprostadil has been shown to enhance the blood circulation through the process of expanding the blood vessels. It is naturally found in the human body and therefore ensures that blood is kept flowing. When saturated at the region around the penis it will induce an erection and maintain it for some time. From 5 to 20 minutes of taking effect, it may last for at least an hour. FDA had this supplement approved in 1996 for the treatment of erectile dysfunction. It is self-injected into the penis shortly before sexual intercourse. The drug creates an erection by relaxing the smooth muscle tissue and dilating the major artery in the penis, which enhances the blood flow to the penis.
Although erectile dysfunction is more commonly caused by diabetes, prostate cancer surgery, especially retroperitoneal dissection, often causes it as well. It can be considered a complication of prostate cancer treatment.