The American College of Emergency Physicians released a study Tuesday of hikers who took ibuprofen before, during and after an ascent to high altitude.

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Overall, 69 percent of people in the placebo group developed AMS, compared with just 43 percent in the ibuprofen group. And symptoms of AMS were less severe in people in the ibuprofen group who did develop the illness, according to study lead author Dr. Grant Lipman of Stanford University School of Medicine.

“We did this study with the mountaineer or those who have limited vacation time in mind, but it certainly has applicability to the warfighter,” Lipman said.
The study consisted of two groups: 44 participants received ibuprofen and 42 got a placebo. They received doses at base camp and another at 11,700 feet. All hiked nearly three miles at altitude, after which they received a third dose. Then they spent the night and took a final dose in the morning.Their symptoms were monitored and tallied through a questionnaire.