Altitude Sickness is a pathological effect of high altitude on humans, caused by acute exposure to low partial pressure of oxygen at high altitude. It is difficult to determine who may be affected by altitude sickness since there are no specific factors such as age, sex, or physical condition that correlate with susceptibility. However most people can ascend to 2,500 meters with little or no effect.
Symptoms often manifest themselves six to ten hours after ascent and generally subside in one to two days, but they occasionally develop into the more serious conditions.
Symptoms of Mild AMS:
Symptoms tend to be worse at night. Mild AMS does not interfere with normal activity and symptoms generally subside within two to four days as the body acclimatizes. As long as symptoms are mil ascent can continue at a moderate rate. When hiking, it is essential that you communicate any symptoms of illness immediately to others on your trip.
Symptoms of moderate AMS:
is the process of adjusting to decreasing oxygen levels at higher elevations, in order to avoid altitude sickness. http://en.wikipedia.org/wiki/Altitude_sickness – cite_note-Acclimatization-16 Extending the time spent at higher altitudes let the body adjust to the oxygen level there, a process that involves the production of additional red blood cells. Once above approximately 3,000 metres most climbers and high-altitude trekkers take the “climb-high, sleep-low” approach.
The only reliable treatment and in many cases the only option available is to descend. Attempts to treat or stabilize the patient in situ at altitude is dangerous unless highly controlled and with good medical facilities.