Sildenafil, sold as the brand name Viagra among others, is a medication
used to treat erectile dysfunction and pulmonary arterial hypertension..
Its effectiveness for treating sexual dysfunction in women has not
Common side effects include headaches and heartburn, as well as
flushed skin. Caution is advised in those who have cardiovascular
disease. Rare but serious side effects include prolonged erections,
which can lead to damage to the penis, and sudden-onset hearing loss.
Sildenafil should not be taken by people who take nitrates such as
nitroglycerin (glycerin trinitrate), as this may result in a severe and
potentially fatal drop in blood pressure.