Altitude Sickness

Altitude sickness, also called Acute Mountain Sickness (AMS) generally occurs above 2,500 meters, but serious altitude sickness is rarely occurs below 3,000 meters. Symptoms range from suffering a mild headache and weariness to a life-threatening situation, where fluid in the lungs (HAPE) or brain (HACE) is built-up. AMS is caused by the body having difficulty adapting to the lower oxygen levels at higher altitudes. Usually this is exacerbated by ascending too quickly but could also be due to individual sensitivities. As AMS can be fatal, it is important to know about the disease, its symptoms, how to prevent them and how to treat AMS.


Acute altitude sickness is the mildest and most common type of altitude sickness suffered, patients usually have a (mild) headache and/or reduced appetite, and possibly nausea. These kinds of symptoms are quite common above 3,000 meters and yet nothing to be worried about, but it is important to tell your guide or if trekking without a guide another group member about your symptoms, and keep close watch that they don’t get worse. You should not Trek alone.

a) Ask the patient to close their eyes and bring a finger to the tip of their nose.
b) If you have doubt of AMS, ask the patient to walk in a straight line.
c) Ask the patient to put on pants (put his leg into one of the legs)