Do doctors see a lot of patients with altitude illness?

No: High altitude illness occurs at high altitudes only, usually in association with mountain climbing.

Wilderness medicine: Since altitude illness goes away when a person comes off the mountain (or the person dies if they continue climbing and gets serious pulmonary edema or cerebral edema--we usually care for them if climbing alongside. Travel and wilderness doctors do prepare many patients for reducing or avoiding altitude sickness. See one if going to high altitude.