Regular Use of Pain Medicines Doesn't Damage Kidneys.

Medically Reviewed by Charlotte E. Grayson Mathis, MD
From the WebMD Archives

July 17, 2001 -- Aspirin and similar pain medicines are such a part of everyday life -- about a quarter of U.S. adults use them weekly -- that most of us assume they're perfectly safe. But for years, doctors have cautioned that regular use of these drugs can cause major damage to your kidneys and cause bleeding in the stomach.

A new study gives us one less thing to worry about: Moderate use of over-the-counter pain relievers isn't likely to lead to kidney problems, the researchers found. However, two doctors who reviewed the study for WebMD believe overuse of pain medicines, particularly over a long period of time, may still be harmful.

The study in July 18 issue of the Journal of the American Medical Association looked at the use of nonprescription pain medicines such as aspirin, acetaminophen (sold under the brand name Tylenol) and non-steroidal anti-inflammatory drugs such as Motrin, Advil, or Aleve in more than 11,000 healthy men over a 14-year period.

They found no increase in kidney problems among men who took an average of three or four pills a week (a total of 2,500 pills during the study period.) The study didn't look at other possible side effects of these drugs such as harm to the liver or gastrointestinal bleeding.

"This study is not necessarily applicable to what happens in the real world, because the amount [of pain medicine] used is not as much as I see people actually taking," says Morrell M. Avram, MD, chief of nephrology at Long Island College Hospital and professor of internal medicine at SUNY Brooklyn. "If you take pain medicines for two or three weeks, I don't think anything is going to happen."

"In this study we weren't looking at high-dose usage [over short periods of time], nor at people who take these medicines four times a day for 14 years, says lead author Kathyrn M Rexrode MD, an associate in the division of preventive medicine at Brigham and Women's Hospital, in Boston. "We were looking at people who have them in their medicine cabinet and use them a couple of times a week for headache or similar aches and pains. That's what we consider normal use. Under those circumstances, we found no increased risk of abnormal kidney function."

People in the U.S. tend to drink too little water, and that puts additional stress on the kidneys, Avram says. "When you look at elderly people who drink only a small amount of water, and also take lots of pain medicines, that's a set-up for disaster."

Avram believes over-the-counter pain medicines do have considerable potential to cause harm, especially if used in massive doses, or in smaller doses over a long period of time.

"Be careful about the length of time you take these medicines and the intensity of dosage," he says. "You should drink lots of water while you're taking pain medicines. Avoid smoking, because substances in smoke [may cause further kidney damage]."

He emphasizes that people should drink water, and not coffee or tea, because those beverages also may further kidney damage caused by pain medicines.