The specific aim of this study is to evaluate if acetazolamide will be similar to ibuprofen (i.e. Ibuprofen being non-inferior) in decreasing the incidence of Acute Mountain Sickness (AMS) in travelers to high altitude. It has been shown that ibuprofen taken 3 times a day 6 hours prior to ascent is effective for the prevention of AMS, with a number needed to treat of 4, decreasing the odds of getting AMS by a third. The efficacy appears to be similar to acetazolamide, with a NNT of 3 -8, although these two medications have not been directly compared in prevention of AMS. Acetazolamide is diuretic that is the only FDA approved AMS prophylactic medication and the most commonly used drug for AMS prevention. Although acetazolamide has been given a 1A indication, it has been shown to limit exercise capabilities at high altitude, and rapid ascent has been shown to attenuate its protective effects. Ibuprofen has been given a IIB recommendation by the Wilderness Medical Society Practice Guidelines, in part because it has not directly compared to acetazolamide. It is unknown if a non-steroidal anti-inflammatory can provide protection from AMS equivalent to acetazolamide.