Altitude Sickness Prevention with Ibuprofen Relative to Acetazolamide

Abstract Background Acute mountain sickness is a common occurrence for travel to high altitudes. Although previous studies of ibuprofenhave shown efficacy for the prevention of acute mountain sickness, recommendations have been limited, as ibuprofenhas not been compared directly with acetazolamideuntil this study. Methods Before their ascent to 3810 m on White Mountainin California, adult volunteers were randomized to ibuprofen(600 mg, 3 times daily, started 4 hours before the ascent), or to acetazolamide(125 mg, twice daily, started the night before the ascent). The main outcome measure was acute mountain sickness incidence, using the Lake Louise Questionnaire (LLQ), with a score of >3 with headache. Sleep quality and headache severity were measured with the Groningen Sleep Quality Survey (GSQS). This trial was registered at ClinicalTrials.gov: NCT03154645 Results Ninety-two participants completed the study: 45 (49%) on ibuprofenand 47 (51%) on acetazolamide. The total incidence of acute mountain sickness was 56.5%, with the incidence for the ibuprofengroup being 11% greater than that for acetazolamide, surpassing the predetermined 26% noninferiority margin (62.2% vs 51.1%; 95% confidence interval [CI], –11.1 to 33.5). No difference was found in the total LLQ scores or subgroup symptoms between drugs ( P  = .8). The GSQS correlated with LLQ sleep ( r  = 0.77; 95% CI, 0.67–0.84)=%. The acetazolamidegroup had higher peripheral capillary oxygen saturation than the ibuprofengroup (88.5% vs 85.6%; P  = .001). Conclusion Ibuprofenwas slightly inferior to acetazolamidefor acute mountain sickness prevention and should not be recommended over acetazolamidefor rapid ascent. Average symptoms and severity were similar between drugs, suggesting prevention of disease.