Viagra and Nitrates Don't Mix
Viagra has come under repeated attention, especially regarding its interaction with nitrates. We feel, nonetheless, that repeating the warning that "Viagra and Nitrates Don't Mix" is important and may, we hope, save the lives of any persons who may now be taking the two types of drugs or may consider doing so in the future.
The US Food and Drug Administration (FDA) has warned against the use of the impotence drug Viagra by persons taking medications that contain nitrates. The FDA's warning was issued in conjunction with Pfizer, the manufacturer of Viagra (generic name: sildenafil).
Viagra and nitrates both cause the muscles that control the size
of blood vessels to relax. When these muscles relax, the vessels
enlarge in diameter and, as a result, blood pressure drops. When Viagra and nitrates are taken together, the effects are greater than
when either one is used alone. There may be a marked relaxation of
the muscles that control the vessels with a great drop in blood