Completing an endurance event, like an ultramarathon or Ironman triathalon, makes you feel immortal. At least fitter, better looking, morally superior and healthier than the average smoker or couch potato.

But if you have to rely on ibuprofen to get through a race, cross “healthier” off your list.

For one thing, if you’re taking it for pain, remember pain means something’s wrong. Endurance athletes have a high tolerance for pain, so if you feel it enough to relieve it, something’s going on.

But more importantly, ibuprofen and endurance sports don’t mix. Here’s why:

Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID), along with aspirin, naproxen sodium and ketoprofen. Notoriously known as Vitamin I, ibuprofen is the NSAID of choice among endurance athletes. Over half the participants in endurance events take ibuprofen, some more than others.

“Ibuprofen is absolutely the most overused pain medication out there,” says Dr. Lisa Bliss, an accomplished ultrarunner and practicing sports medicine doctor. Over the past decade, Dr. Bliss has served as Medical Director for the Western States 100 and Badwater 135 endurance runs. She should know.

Ibuprofen, like any other NSAID, works by inhibiting the production of prostaglandins in the body. Prostaglandins are hormones that help mediate pain and inflammation. They also protect the stomach lining and regulate blood pressure. Plus, prostaglandins are involved in the production of collagen, the building blocks of skin, muscle and other body parts. Inhibiting prostaglandins inhibits everything they do.

So not only does taking ibuprofen mask pain to allow further injury, it can delay recovery. Studies have shown ibuprofen slows the healing of injured muscles, tendons, ligament and bones.

“Ibuprofen also inhibits COX-2, one of the enzymes that protects the heart,”  Bliss adds, “which may increase the risk of heart attack.”

Taken regularly, ibuprofen can cause stomach irritation or gastrointestinal bleeding. Ibuprofen use can lead to low-level endotoxemia, where bacteria leak from the colon into the bloodstream. Not a good thing to have when your immune system is already suppressed by strenuous activity.


Endurance athlete and SWEAT Publisher Sue Berliner ended her close and personal relationship with ibuprofen after learning it was the cause of unpleasant side effects.

“In the late  90's through 2000 I ran many marathons and ultramarathons successfully,” Berliner explains. “It was standard operating procedure to pop a few ‘Vitamin I’ pills before each event. I would take two or three before an event and maybe one to two during a race. I did not heavy dose on them or use them during training. Mostly after the marathons I would wind up with a case of intestinal bleeding for a day or two. Not pretty. I did not connect the dots but knew something was wrong with this picture. I stopped running and still struggled to recover from a hamstring injury. A doctor friend enlightened me on the issues with ibuprofen and I went cold turkey. I was back on the road running soon after.”

Ibuprofen also impairs kidney function by constricting the blood vessels into the kidneys.

Dehydration alone is hard on the kidneys, but don’t think drinking more water balances things out. Water can wash out electrolytes, and ibuprofen complicates the issue.

Studies show taking ibuprofen during ultra distance training or races may increase the risk of hyponatremia, or low blood sodium. In extreme cases, hyponatremia can lead to coma and death. In most cases, it leads to a DNF.

Strenuous exercise causes muscle breakdown, releasing myoglobin into the bloodstream. The kidneys filter these toxic proteins out, but when too much myoglobin floods the kidneys, it can clog up the blood vessels and cause kidney failure. Add ibuprofen into the mix, and that failure could come sooner than later. Especially if you’re slightly dehydrated. More than a few athletes have learned this lesson the hard way.

The negative effects of ibuprofen on athletes have been studied and reported since the mid-1990s. While most endurance athletes know about the consequences, many continue to take the risk.

Is there a safer alternative?

“Ice is nice,” says Bliss. “It naturally relieves pain and reduces inflammation. It helps recovery for your next run. Just don’t get a freeze burn.”

If you really need pain relief during an event, Bliss recommends taking acetaminophen, the active ingredient in Tylenol. But she cautions to stay below half the recommended daily dose since acetaminophen can affect the liver and endurance activity can too.

For a more natural approach, Berliner says “I sought natural supplements that actually reduce inflammation in the body. I have been taken Windhawk's Anti-Inflammatory supplement morning and night and during long workouts since the company developed the product a few years back. No intestinal problems and I train and race pain free.”

Of course, if you’ve been habitually popping ibuprofen through every event you’ve done and nothing’s happened, nothing ever will. Until you find you haven’t peed after a race, start feeling sick and end up in the hospital, looking like a beached whale hooked up to dialysis. Then all those smokers and couch potatoes you thought you were better than are better off than you.