Symptoms generally associated with mild to moderate altitude illness include:

·         Difficulty sleeping

·         Dizziness or light-headedness

·         Fatigue

·         Headache

·         Loss of appetite

·         Nausea or vomiting

·         Rapid pulse (heart rate)

·         Shortness of breath with exertion

Symptoms generally associated with more severe altitude illness include:

·         Bluish discoloration of the skin (cyanosis)

·         Chest tightness or congestion

·         Confusion

·         Cough

·         Coughing up blood

·         Decreased consciousness or withdrawal from social interaction

·         Gray or pale complexion

·         Inability to walk in a straight line, or to walk at all

·         Shortness of breath at rest