Altitude Sickness

Altitude sickness, also called mountain sickness, is an illness that can affect mountain climbers, hikers, skiers, or travellers at altitudes above 2,400 meters.


Mountain sickness is caused by the failure of the body to adjust to reduced air pressure and lower oxygen levels at high altitudes. The faster you gain altitude, the more likely that you will suffer an attack. You are also at higher risk for mountain sickness if:

  • You live at or near sea level and travel to a high altitude.
  • You suffer from motion sickness.
  • You have not acclimatized to the altitude.
  • Alcohol or other substances have interfered with acclimatization.
  • You have medical problems involving the heart, nervous system, or lungs.


Mild mountain Sickness

In most cases, the malady is mild. Symptoms of mild to moderate mountain sickness may include any one or more of the following:

  • Light-headedness
  • Headache
  • Disturbed sleep
  • Dizziness
  • Fatigue
  • Loss of appetite
  • Nausea or vomiting
  • Rapid heart rate
  • Shortness of breath

The symptoms often disappear when no father altitude is gained or if one descends. However, if one asserts themselves or climbs too fast, the mountain sickness may become acute and life-threatening as it affects the nervous system, lungs, and heart.

Acute Mountain Sickness

Symptoms of acute mountain sickness include:

  • Chest tightness or congestion
  • Confusion
  • Coughing
  • Coughing up blood
  • Decreased consciousness
  • Inability to walk in a straight line
  • Unable to walk
  • Shortness of breath at rest


The main treatment for all forms of mountain sickness is to descend to a lower altitude as rapidly and safely as possible. You should not continue climbing if you develop symptoms without allowing for the symptoms to disappear. Extra oxygen may be given, but the patient must still descend to a lower altitude to allow for acclimatisation.

If symptoms persist, seek medical attention. Acetazolamide may be given by a medic.


  • Climb the mountain gradually. Walk even if a road is provided.
  • Insert an extra day in your itinerary for every altitude gain of 600 to 1000m.
  • Hike high Sleep at a low.
  • Stop immediately symptoms are recognised and wait for them to subside
  • Drink plenty of non-alcoholic fluids.
  • Eat regular meals that are high in carbohydrates.

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