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Altitude sickness


Altitude sickness is defined as the negative health effect of high altitude (>2700m) that occurs when there is a rapid exposure to low amounts of oxygen at a high elevation. Acute Mountain Sickness (AMS) is the mildest form of altitude sickness. Due to less available oxygen at high altitude, the human body has to work harder to adapt  to the atmosphere. As you go higher, the heart and lungs are under a significant amount of strain and sometimes the body is unable to keep up. Fluid accumulates in the body where it does not belong.

Common Symptoms of AMS:

  • Head-ache
  • Nausea
  • Loss of appetite
  • Fatigue
  • Dizziness

Sometimes the symptoms of AMS can be confused with dehydration and over-exertion. This is why it is important to familiarize yourself with mountain sickness or high altitude sickness if you are a trekker or a mountaineer so that you may be better able to help yourself and others.

If AMS is left untreated, the condition can worsen and progress into high altitude cerebral edema (HACE) and high altitude pulmonary edema (HAPE).

High Altitude Pulmonary Edema (HAPE): With the onset of AMS, as fluid collects in the lungs, you become breathless more easily while walking, and eventually more breathless at rest. A cough begins, initially dry and irritative, but progressing to the production of pink, frothy sputum in its most severe form. The patient eventually drowns in this fluid if he or she doesn’t descend.

High Altitude Cerebral Edema (HACE): When fluid collects in the brain, you develop a headache, loss of appetite, nausea, and sometimes vomiting. You become tired and progressively develop a problem with balance and coordination.

Both conditions can be fatal.

How Can I Prevent AMS?

– Walk slowly and take breaks. Take time to acclimatize. Do not rush up the mountain.

-Drink plenty of fluids. 4-6 litres of fluid (water, soup,tea,etc) is the recommended amount.

-Avoid alcohol or sedative drugs as these can depress the respiratory system.

-Listen to your body and speak to your guide as well as peers if you don’t feel well.

-Follow expert advice.

-Talk to your doctor about taking Diamox.

If you do develop signs of AMS, you should take 250mg of Diamox twice a day (provided you don’t have a sulpha allergy) and see if you feel better. You must continue the dose until the highest altitude is reached. It is obviously prudent to get more medical advice. The best treatment for severe altitude sickness (HAPE and HACE) is mandatory descent.  

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