Medical guides on AMS, acclimatization, HACE and HAPE for mountaineers and trekkers.
How much oxygen is there on Mount Whitney, Rainier, Denali and Colorado 14ers? Real SpO₂ data, altitude tables, and altitude sickness risk for US hikers.
Garmin and Apple Watch measure SpO2 — but how accurate are they at altitude? What readings to expect, when to worry, and when to use a dedicated oximeter.
At 3,000 m only 69% of sea-level oxygen is left; at 5,000 m, 53%. Full percentage chart by elevation with air pressure in hPa, on the ISA model.
Complete guide to acetazolamide (Diamox) for altitude sickness prevention and treatment: how it works, correct dosage, side effects, contraindications, and when to start.
HACE (cerebral edema) and HAPE (pulmonary edema): life-threatening altitude emergencies. Recognize symptoms, treat in the field, know when to descend.
At 8,848 m only 31% of sea-level oxygen is available. Discover the data on partial pressure, climbers' SpO₂ readings, and why the Death Zone is lethal.
Complete guide to AMS: symptoms, risk factors, prevention and treatment. Based on UIAA and WMS 2024 guidelines.
At 4,000 m SpO₂ falls to 85–90%. At 5,000 m: 75–82%. Full chart every 500 m — from sea level to Everest — with AMS thresholds and descent criteria.
