Severe facial edema at high altitude.

We present a complication associated with high altitude of unusual severity. Pronounced facial edema developed in a 27-year-old woman during a trek to Kilimanjaro, Tanzania. The development of facial edema has previously been documented in visitors unaccustomed to high altitude. The possible pathophysiological mechanisms are discussed, and the importance of adhering to recommended ascent rates is emphasized for all high-altitude treks.