From the Guidelines
To prevent altitude sickness, the most effective approach is gradual ascent, allowing your body to acclimatize by ascending no more than 1,000-1,500 feet per day above 8,000 feet, with a rest day every 3,000 feet, as recommended by recent guidelines 1. When traveling to high altitude destinations, it is essential to be aware of the potential risks and take preventive measures to minimize them. High altitude represents a natural stress due to low oxygen partial pressure and barometric pressure, which can lead to high altitude retinopathy (HAR) and other complications.
Prevention Strategies
- Stay hydrated and avoid alcohol to reduce the risk of dehydration and exacerbation of altitude sickness symptoms.
- Consider taking acetazolamide (Diamox) 125-250mg twice daily starting 24 hours before ascent and continuing for 48 hours after reaching your final altitude, as it can help increase respiratory drive and reduce cerebral edema 1.
- For high-risk individuals, dexamethasone 4mg every 6 hours can be used as a preventive measure.
Treatment Options
If symptoms of altitude sickness develop, the primary treatment is immediate descent of at least 1,000-3,000 feet.
- For mild symptoms, rest, hydration, and over-the-counter pain relievers like ibuprofen or acetaminophen can help alleviate symptoms.
- Moderate to severe cases may require supplemental oxygen (2-4 L/min), acetazolamide (250mg twice daily), or dexamethasone (4mg every 6 hours) to reduce symptoms and prevent further complications.
- Portable hyperbaric chambers can temporarily simulate descent when immediate physical descent isn't possible, providing a temporary solution until medical attention can be obtained. It is crucial to note that individuals with pre-existing cardiovascular conditions, such as heart failure, should exercise caution when traveling to high altitudes and consult with their healthcare provider before ascending 1.
From the Research
Prevention of Altitude Sickness
- The major preventive measure for altitude sickness is slow ascent 2
- Acetazolamide is effective in preventing acute mountain sickness (AMS) 2, 3, 4
- Dexamethasone is also effective in preventing AMS 2
- Nifedipine is effective only against high-altitude pulmonary edema (HAPE) and not against AMS 2, 5
Treatment of Altitude Sickness
- Immediate descent and/or the administration of oxygen is the treatment of choice for both AMS and HAPE 2, 6
- Dexamethasone may be given for severe AMS 2
- Nifedipine may be given for HAPE 2, 5
- Acetazolamide may be used for treatment of AMS, with doses of 500-750 mg/day appearing to be the most effective for minimizing symptoms 3