How safe are NSAIDS for the aches and pains of exercise?

Very few of us have not relied at one time or another on an NSAID or non-steroidal anti-inflammatory drugs for treating pain or a fever.  In fact, NSAIDS are the most prescribed medications for treating conditions such as arthritis, headaches, and back pain.  Most of us are familiar with over-the-counter nonprescription NSAIDS, such as aspirin and ibuprofen.  There are more than a dozen different NSAIDS available.  Besides pain, NSAIDS they can also relieve inflammation and prevent blood from clotting which can be beneficial for some but not for others.

Athletes are common users of NSAIDS – they use them to help relieve the aches and pains of exercise that many experience.  For example, marathoners and other endurance athletes will use NSAIDS preventively to reduce pain and possibly improve performance.  But now a new study is saying that athletes who routinely use NSAIDS may be at a particular risk for injury to the kidneys. 

How safe are NSAIDS?

NSAIDS do have a good safety profile especially when taken in small doses for short periods of time.  But like any medication, NSAIDS can and do have side effects particularly if they are taken in high doses and for prolonged use.  The side effects can range from upset stomach, intestinal bleeding, and cardiovascular problems.  To this list can also be added the risk of heart attack especially if one has had a previous heart attack and also risk of kidney injury.  Generally, people who develop injury to the kidneys, already have kidney disease or are taking medications that can affect kidney function. 

Study on NSAIDS and exercise

A study which appeared in the July 2017 edition of Emergency Medicine Journal, set out to find the effect of NSAID use on acute kidney injury incidence in ultramarathon runners. 

For the study, 89 ultramarathoners, who participated in one of several seven-day 155-mile races, were divided into two groups – one group took 400 mcg of ibuprofen (equivalent to two over-the-counter Advil) every four hours for three or four doses toward the end of the race, while the second group took a placebo.

Findings from the study showed the following:

·      The incidence of injury to the kidneys was common – 44% of participants experienced significantly reduced kidney function by the end of the race.

·      The participants who took ibuprofen had the most kidney injury with a little over half of the NSAID-users had reduced kidney function, while only one-third of those in the placebo group who did. 

·      The ultramarathoners who took the NSAIDS had a greater degree of severity of kidney injury.

·      What appeared to increase the likelihood of injury to the kidneys were marathoners who finished the races the fastest and had a greater loss of weight after the race most likely due to dehydration.

It should be noted that dehydration and muscle damage are common among endurance athletes which can contribute to kidney injury.

How does this apply to the average exerciser?

For the typical adult exerciser who does not run 155 miles a week, the results of this study may not apply.  Plus, this was a small study, it did not examine the long-term effects of ibuprofen on kidney function and a higher or lower dose of ibuprofen may have produced different results.

The main takeaway is that this study does point out concerns of taking ibuprofen during exercise, at least among endurance athletes.  A better alternative, as suggested by the study authors, is to use acetaminophen (Tylenol) even though more research is needed to test the safety of even alternatives like it.

The best advice is to check with your doctor first to make sure you are a good candidate for NSAID use to begin with.  Anyone using NSAIDs regularly should have their blood monitored along with checking on their kidney function.  For those who already have kidney disease, will most likely be advised to avoid NSAIDS altogether.