altitude sickness

altitude sickness

Acute reaction to a change from low altitudes to altitudes above 8,000 ft (2,400 m). Most people gradually adapt, but some have a severe reaction that can be fatal unless they return to low altitude. Normal adaptations to the reduced oxygen at high altitude (e.g., breathlessness, racing heartbeat) are exaggerated; other manifestations include headache, gastrointestinal upsets, and weakness. Pulmonary edema is quickly reversed with oxygen and evacuation to a lower area.


altitude sickness or mountain sickness

This entry comes from Encyclopædia Britannica Concise.
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