Mountain Sickness (Altitude Sickness)

What is mountain sickness?

There is less air at higher altitudes. If you suddenly move from a low to a high altitude, you may feel unwell, because less oxygen reaches your body's tissues. Symptoms associated with this are called mountain sickness.

Who is affected by mountain sickness?

Mountain sickness affects climbers, hikers, or skiers as well as people flying into airports at high altitude because this does not allow acclimatisation.

What causes mountain sickness?

Reduced atmospheric pressure and oxygen pressure at high altitude are causes of this illness. It is mainly caused by too rapid an ascent. It affects the nervous system, lungs, muscles and heart. Holiday flights straight into airports at high altitude, which do not allow time for acclimatisation also cause mountain sickness. For example Le Paz in South America and East Africa.

What are the symptoms of mountain sickness?

Symptoms occur due to our body not adapting well to having less oxygen at high altitude. They include:

  • Dry Coughing.
  • Fatigue.
  • Dizziness.
  • Headache especially when you first wake up, which can be aggravated by coughing.
  • Sleeping difficulty.
  • Nausea, vomiting and confusion.
  • Coughing up blood.
  • Shortness of breath.
  • Loss of appetite.
  • In sever cases facial swelling, pupil dilation and vision abnormalities may be symptoms.

How is mountain sickness treated?

For mild symptoms, you can stay at the same altitude to allow symptoms to subside, before ascending. If symptoms worsen, you should consider descending.

For severe symptoms, descent must begin as soon as possible. Helicopter evacuation may be essential. This is to avoid physical exertion, which can prove fatal for a sufferer. Hospitalisation may be required in severe cases. Supportive measures include oxygen by mask or by mechanical ventilation.

How can the risk of mountain sickness be avoided?

  • Educate yourself on the symptoms of mountain sickness.
  • Ascend gradually, stopping for rest for each 2000 feet.
  • Serious climbing groups should carry an oxygen supply sufficient for several days.
  • People with underlying cardiac or pulmonary lung disease should avoid high altitudes.
  • When flying into any high altitude destination eg. Mexico City, you should avoid physical exertion for the first day. You should drink plenty of water and avoid smoking.
  • If symptoms persist you should obtain professional advice.

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