Whether you're an avid mountaineer planning your next summit bid above 2500 meters (8,200 feet) or a weekend warrior looking to bag some 4300-meter (14,000-foot) peaks, altitude illness is a risk we all face when venturing above 2400 meters (8,000 feet). As new research emerges, expert recommendations evolve on how best to prevent and treat acute mountain sickness (AMS), high altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE)—the three forms of altitude illness that can occur.
AMS, the most common form, causes symptoms like headache, nausea, fatigue, and poor sleep in the first few days after rapid ascent. It's unpleasant but typically self-limited. HACE and HAPE represent progression to life-threatening illness characterized by fluid in the brain or lungs, respectively. Knowing how to prevent and recognize these disorders is critical.
The Wilderness Medical Society recently released updated clinical practice guidelines for prevention and treatment of altitude illness. As a lover of high places, what do you need to know about the new recommendations?
First, be flexible in applying the guidelines based on elevation. Rigid cutoffs aren't perfect. Focus more on your symptoms and ascent rate. Gradual ascent is still the cornerstone for prevention.
For medications, the recommended doses and durations are more specific. If you're at high risk for AMS, consider a higher dose of acetazolamide. Alternate dexamethasone and acetazolamide, but don't use both routinely. For HAPE prevention, pulmonary vasodilators like nifedipine may be needed longer when ascending quickly.
On the treatment side, acetazolamide now has a formal role for moderate-severe AMS. Phosphodiesterase inhibitors like sildenafil are reasonable alternatives if nifedipine is unavailable for HAPE. One caution: avoid using multiple vasodilators together due to hypotension risk.
Had COVID-19 recently? Make sure to get evaluated for exercise limitations before a big trip above 3000 meters (10,000 feet). Lingering lung or heart effects may increase your susceptibility to altitude illness.
While core tenets remain unchanged, having more tailored preventive protocols and treatment options is welcome news. By combining the updated medical expertise with your own experience and judgment, you can continue to summit safely. Tradition states the mountains will always be here - we just need to take the proper precautions to make sure we are too.
Don't forget we have a handy free fact sheet that provides a great overview of altitude illness and its prevention and treatment.
Let the guidelines help as you go forth and embrace the adventure! What new summits will you conquer? Let us know in the comments your plans for the coming hiking, climbing, or ski season and how these recommendations might influence your approach.
Going High - Höghöjdsmedicin för entusiaster
Going High covers the healthy and ill body at altitude. Whether you are curious about what happens when you travel to higher altitudes, or want to be properly prepared as the leader of an expedition, Going High is a book for you.