High-altitude illness (HAI) encompasses an array of conditions that may occur in individuals who travel to high elevations, including acute mountain sickness, high-altitude cerebral edema, and high-altitude pulmonary edema. Individuals with a history of HAI are predisposed to developing HAI; however, other risk factors are not well defined. The primary method of preventing HAI is acclimatization through gradual ascent to high altitude. In addition, many studies have assessed the use of pharmacologic prophylaxis. The most studied and widely recommended prophylactic agent is acetazolamide; additional agents that have been considered include dexamethasone, Gingko biloba, antioxidant vitamins, nifedipine, aspirin, and salmeterol. The treatment of choice for all forms of HAI is descent to lower altitude. The use of additional treatments, including supplemental oxygen, varies depending on the severity of the clinical presentation. Acetazolamide and dexamethasone have been studied as adjunctive treatments for acute mountain sickness, while nitric oxide and nifedipine have been evaluated for the treatment of high-altitude pulmonary edema. Data with analgesics and phosphodiesterase-5 inhibitors, while limited, are promising. This review will present the evidence supporting the use of pharmacotherapy for prevention and treatment of HAI.
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