If you’ve ever experienced altitude sickness, then you know what Grant Lipman, MD, a clinical assistant professor of surgery and emergency medicine at Stanford School of Medicine in California, is talking about when he describes it as “a nasty hangover.”

Headaches, fatigue, dizziness, nausea, vomiting and loss of appetite are all par for the course for those who hike, camp, ski or just hang out at high altitudes every year.

This is because atmospheric pressure is lower the higher you get, so every breath you take contains less oxygen than it would at sea level.

(These symptoms can sometimes be confused with symptoms of dehydration, so always drink lots of water before and during any trip to a high altitude.)

Standard treatments for altitude sickness are prescription medications, so it takes some time to get a hold of them—plus they sometimes trigger uncomfortable and/or serious side effects.

The promising news is that Dr. Lipman’s latest research suggests that there may be an easy, safe way to prevent altitude sickness from occurring in the first place—or at least reduce its severity. It involves taking an over-the-counter pill that has few side effects and is probably already in your medicine cabinet.

A FORM OF PREVENTION THAT REACHES NEW HEIGHTS

Dr. Lipman set out to find a preventive drug for altitude sickness because the current treatments (prescription drugs known as acetazolamide and dexamethasone) have drawbacks. Acetazolamide can cause nausea, dizziness and fatigue. Meanwhile, dexamethasone has been associated with high blood sugar, delirium, depression, insomnia, mania and more. So Dr. Lipman decided to study the over-the-counter medication ibuprofen because he thought it might reduce the swelling in the brain that occurs when we don’t take in enough oxygen—and because it causes few side effects.

Researchers recruited volunteers who were willing to hike up a mountain. All were healthy. They spent the first night at 4,100 feet and then took either 600 milligrams (three 200-milligram tablets) of ibuprofen or a placebo at 8 am before driving up the mountain to a designated spot at 11,700 feet. There, they received a second dose at around 2 pm, then they hiked to 12,570 feet where they received a third dose at 8 pm and made camp. They got a final dose the next morning before returning to their starting altitude.

Results: Among the hikers who received the placebo, 69% experienced symptoms of altitude sickness over the course of the study. In contrast, only 43% of the hikers who took ibuprofen had symptoms. In other words, those in the study who took ibuprofen were much less likely to experience altitude sickness.

Also, the ibuprofen takers who did get sick reported slightly less severe symptoms compared with the placebo group. Although the researchers didn’t test altitude sickness prescription drugs in this study, they noted that ibuprofen’s efficacy rate seemed to be on par with them. And recipients needed to take the ibuprofen only six hours before reaching higher ground—as opposed to acetazolamide, for example, which must be taken a full day before.

AIN’T NO MOUNTAIN HIGH ENOUGH

Further study is required before Dr. Lipman will know whether ibuprofen works at altitudes higher than 12,570 feet, works for prolonged periods or works while people participate in other activities (skiing versus hiking, for example).

“But ibuprofen has a great safety profile, so I’d recommend taking it at altitudes up to about 12,500 feet,” he says. So whether you’re hitting the slopes, hiking or visiting friends in Denver, consider taking a 600-milligram dose of ibuprofen the morning of your ascent. You probably won’t need to take it on the descent—altitude sickness usually goes away as you reach lower ground. “But if you feel sick on your way down, keep taking ibuprofen every six hours until you reach the last altitude you felt well at,” Dr. Lipman suggested.

As safe as ibuprofen generally is, please do check with your doctor first, especially if you have ulcer or kidney problems, because ibuprofen can exacerbate acid reflux and stomach and kidney problems (particularly if you’re dehydrated).

If it’s safe for you to take ibuprofen, you might just find yourself breathing a little easier—all the way up to the mountaintop.