n.
First oral drug for male impotence , generic name sildenafil.
Before the FDA approved Viagra in 1998, impotence was treated with surgical implants, suppositories, pumps, and drugs injected into the penis. Taken as a pill shortly before sexual intercourse, Viagra selectively dilates blood vessels in the penis, improving blood flow and allowing a natural sexual response. It works in about 70% of cases; it should not be used by anyone taking nitroglycerin or with heart problems, hypotension, hypertension, recent stroke, or certain eye disorders.