NSAIDs — or nonsteroidal anti-inflammatory drugs — are among the most
common pain relief medicines in the world. Every day more than 30 million
Americans use them to soothe headaches, sprains, arthritis symptoms, and other
daily discomforts, according to the American Gastroenterological Association.
And as if that wasn’t enough, in addition to dulling pain NSAIDs also lower
fever and reduce swelling.
But how do those little pills do so much? And if they’re so good in some
ways, why do they also raise the risk of heart problems in some people? The
answer is complicated. Even researchers don’t fully understand how NSAIDs
work.
Nonetheless, with the benefits and risks of NSAIDs in the headlines
frequently, WebMD turned to four experts for a rundown of what researchers do
know. Our panel consisted of:

Byron Cryer, MD, a spokesman for the American Gastroenterological
Association and an associate professor of medicine at the University of Texas
Southwestern Medical Center in Dallas.
Nieca Goldberg, MD, a spokeswoman for the American Heart Association and
chief of Women’s Cardiac Care at Lennox Hill Hospital in New York.
John Klippel, MD, president and CEO of the Arthritis Foundation in
Atlanta.
Scott Zashin, MD, clinical assistant professor at the University of Texas
Southwestern Medical Center in Dallas and author of Arthritis Without
Pain.

Here is their explanation of how NSAIDs help ease your pain — and sometimes
cause side effects in the process.
What Is Pain?
First, it helps to understand what pain is. On a basic level, pain is the
result of an electrical signal being sent from your nerves to your brain.
But the process is not only electrical. When you get injured — say with a
sprain — the damaged tissue releases chemicals called prostaglandins, which
are like hormones. These prostaglandins cause the tissue to swell. They also
amplify the electrical signal coming from the nerves. Basically, they increase
the pain you feel.
How Do NSAIDs Help Relieve Pain?
NSAIDs work on a chemical level. They block the effects of special enzymes
– specifically Cox-1 and Cox-2 enzymes. These enzymes play a key role in
making prostaglandins. By blocking the Cox enzymes, NSAIDs stop your body from
making as many prostaglandins. This means less swelling and less pain.
Most NSAIDs block both Cox-1 and Cox-2 enzymes. They include the
over-the-counter drugs:

Aspirin (Bufferin, Bayer, and Excedrin)
Ibuprofen (Advil, Motrin, Nuprin)
Ketoprofen (Actron, Orudis)
Naproxen (Aleve)

Other NSAIDs are available by prescription. They include:

Daypro
Indocin
Lodine
Naprosyn
Relafen
Voltaren

Aspirin has some benefits that other NSAIDs do not. The biggest is that
aspirin works against the formation of blood clots. As a result, you are less
likely to form the clots that can cause heart attacks and strokes. Other NSAIDs
do not have this effect.
Cox-2 inhibitors are a newer form of prescription NSAID. As you might guess,
they only affect Cox-2 enzymes and not Cox-1. Two of them — Bextra and Vioxx
– are no longer sold because of concerns about their side effects. The third,
Celebrex, is still available.

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