Symptoms of altitude sickness

Symptoms of altitude sickness usually develop between6 and 24 hours after ascending to high altitude.

Mild altitude sickness

Common symptoms of mild altitude sickness (sometimes called acute mountain sickness) can be similar to a bad hangover and may include:

  • headache
  • nausea and vomiting
  • dizziness
  • tiredness
  • loss of appetite
  • upset stomach
  • feeling unsteady
  • shortness of breath
  • increased heart rate
  • difficulty sleeping
  • generally feeling unwell

The symptoms are usually worse at night.

Severealtitude sickness

Signs of severe altitude sickness can include:

  • worsening of the symptoms describedabove
  • a persistent, irritablecough
  • breathlessness (even when resting)
  • a bubbling sound in the chest
  • coughing up pink or white frothy liquid
  • clumsiness and difficulty walking
  • irrational behaviour
  • double vision
  • fits (convulsions)
  • drowsiness
  • confusion

Severe symptoms could mean you're developing cerebral oedema or pulmonary oedema. These are potentially life-threatening complications of altitude sickness.

What to do if you have symptoms

If you have symptoms of mild altitude sickness, don'tgo any higherfor 24 to 48 hours. If your symptoms don't improve or get worseduring this time, you should descend immediately.

Severe altitude sickness is a medical emergency. Someone with severe symptoms should immediately descend to a low altitude and seek medical help.


Content supplied by the NHS Website

Medically Reviewed by a doctor on 30 Apr 2015