Introduction
Acute Mountain Sickness (AMS) afflicts 50% to 80% of high-altitude travelers, and can be debilitating. AMS is defined as headache with nausea/vomiting, fatigue/weakness, dizziness/lightheadedness, and/or difficulty sleeping because of rapid ascent. Becaue patients with AMS often are nauseated, metoclopramide may be a solution, as it treats nausea and migraine headaches. Studies also suggest ibuprofen as effective AMS therapy.
Objective
Assess the effectiveness of metoclopramide compared with ibuprofen for AMS treatment.
Methods
We performed a prospective, double-blinded, randomized, field-based clinical trial of 10 mg metoclopramide vs 400 mg ibuprofen for AMS treatment. Enrollment was March to May 2013 and March to April 2015 along the approach to Mount Everest in Pheriche (4280 m) and Dingboche (4358 m), Nepal. Eligibility criteria were ≥1000 vertical feet gain over 24 hours with a headache and one other AMS symptom. Patients with severe AMS, high altitude cerebral edema, or high-altitude pulmonary edema were excluded. Subjects were assessed by vital signs, Lake Louise Score (LLS), and a Visual Analog Scale for headache and nausea severity immediately prior to treatment, and then serially at 30, 60, and 120 minutes afterwards. Results were analyzed by signed-rank and Wilcoxon rank-sum tests (P values < .05 considered significant).
Results
Analysis revealed no significant differences between metoclopramide and ibuprofen groups with respect to age, sex, initial LLS, heart rate, or oxygen saturation. Both medications significantly reduced headache severity and nausea compared with initial headache and nausea over the 2-hour study. At 120 minutes, metoclopramide additionally reduced nausea to a greater degree than ibuprofen, although both medications reduced overall AMS symptoms. When the LLS was used, there was a significant decrease in headache, dizziness, and total LLS with ibuprofen compared with metoclopramide.
Conclusion
Both medications effectively reduced AMS symptoms, including headache and nausea. Metoclopramide additionally reduced nausea more than ibuprofen. Therefore, metoclopramide may be an effective alternative AMS treatment, especially for patients with nausea.
Funding
WMS Houston Grant (2016).