What are symptoms of acute mountain sickness?

Symptoms of acute mountain sickness (AMS) typically develop within the first 1-2 days of ascent to high altitudes, and may include:

Headache: Mild to severe, constant, throbbing or dull head pain.

Nausea and vomiting: Upset stomach, nausea, feelings of sickness, or actual vomiting.

Fatigue and weakness: Feeling tired, lethargic, or easily fatigued.

Shortness of breath: Difficulty breathing, rapid or shallow breathing, even when resting.

Loss of appetite: Reduced desire for food or feeling full quickly.

Dizziness or lightheadedness: Feeling dizzy, wobbly, or lightheaded, especially upon standing up.

Insomnia or disturbed sleep: Difficulty falling or staying asleep, frequent awakenings.

Mental confusion or impairment: Disorientation, difficulty thinking clearly.

Rapid heart rate: Increased heart rate, especially during physical exertion.

Swelling in the face, hands, or feet (facial or peripheral edema): Fluid retention or puffiness.

Feeling of being drunk: Ataxia, uncoordinated movements and imbalance, similar to the effects of alcohol.