Skip to content
Stanford University School of Medicine

Ibuprofen doubles risk of kidney injury in distance runners, Stanford study says

Like the other runners in my office, the first question that popped to mind when I heard about a Stanford study linking kidney damage with ibuprofen use in distance runners was, "Could this apply to me?"

Apparently, I'm not the only runner in the world who has taken ibuprofen — better known by the trade names Motrin or Advil — for pain relief and to reduce joint swelling. The good news is, for someone like me who puts in regular three-mile jogs, the answer is no. The bad news is, maybe that study just hasn’t been done yet.

Grant Lipman, MD, director of Stanford Wilderness Medicine and an extreme athlete himself, began to notice while working as medical director for RacingThePlanet ultramarathons that racers were popping the nonsteroidal anti-inflammatory drug like M&M’s before during and after these intense events. He wanted to know if this was a safe practice.

"Running these races tends to hurt," said Lipman — probably an extreme understatement. These particular ultramarathons are 150-mile weeklong races over rough terrain in deserts around the world from China to Chile to Antarctica. In a press release, Grant explains how extreme running damages the kidneys, even without taking ibuprofen:

Acute kidney injury is common in these athletes due to the high rates of dehydration that cause reduced blood flow and rhabdomyolsis — a breakdown of muscle tissue that leads to the release of muscle fiber contents into the blood, which is harmful to the kidney and often causes kidney damage, Lipman said. In fact, acute kidney injury has been recorded in 34 to 85 percent of all ultramarathoners, the study said.

While most cases of acute kidney injury appear to resolve spontaneously within a few days, the condition has the potential to progress to renal failure. In this study, which appears in the Emergency Medicine Journal, Lipman and colleagues set out to determine whether adding ibuprofen into this mix further increases the danger of kidney damage. "In medical school, we were all taught to be careful of ibuprofen because it decreases blood flow to the kidneys," Lipman told me. However, almost all previous studies looking at the effect of the drug on the kidneys in running events have shown no negative effects, he said.

Lipman and his fellow researchers conducted the first randomized, placebo-controlled double-blinded study to test the use of ibuprofen by setting up a medical tent at the beginning and the end of a 50-mile section of several of these ultramarathon events. Eighty-nine runners who participated in the study were randomized to either ibuprofen or a placebo. He explained:

The morning of this 50-mile section of the race, the participants came to the medical tent. We weighed them and gave them a baggie and said to take these pills every four hours. They were given either 400 milligrams of ibuprofen or sugar pills. Nobody knew which. And instructed to take one every four hours. And they ran off.

At the end of the race, the participants were met at the medical tent by the researchers who weighed them, measured their electrolyte levels and renal functioning. Results showed that about 39 of the 89 participants had acute kidney injury. There was an 18 percent higher rate of kidney injury among those who took the drug compared to those who didn’t, the study found. It wasn't what Lipman was expecting:

'I felt surprised and a little shocked that it really is as bad for you as we found,' said Lipman, who has now switched to using acetaminophen, such as Tylenol, for pain relief and taking ice baths after racing. 'I feel it's ironic to preach moderation in extreme sports, but moderation is probably a safe approach. If something hurts, these athletes might want to consider taking acetaminophen instead.'

Previously: To prevent altitude sickness, same day medication may help, Battling the scourge of blisters, Stanford study shows paper tape can help and Step away from the aspirin, inflammatory molecule boosts muscle-regeneration say Stanford scientists
Photo of Grant Lipman by Paul Sakuma

Popular posts