While you are in trekking or expedition in Nepal, you are bound to go to high altitudes. Annapurna circuit trek takes you to Thorang La with maximum altitude of 5416m and Everest basecamp trek will take you to Kalapatthar with maximum altitude of 5,545m. Similarly Annapurna bascamp trek will take you to a height of 4,137m and Langtang valley trek will have maximum elevation of 3,700m. No matter where you trek, there is a real chance that you might encounter High altitude sickness.

High Altitude Sickness

High altitude sickness is also known as AMS (acute mountain sickness), altitude sickness, hypobaropathy or soroche. It is an effect on human body caused by high altitude. Its due to the exposure of human body to low pressure of oxygen at high altitude. Acute mountain sickness in its severe stage can progress to High Altitude Pulmonary Edema (HAPE) or High Altitude Cerebral Edema (HACE). Both HAPE and HACE are life threatening and should be considered a serious condition.


  • Dehydration due to higher rate of water vapor loss from lungs
  • Due to rapid ascent while trekking
  • Low availability of oxygen at higher altitude

Primary symptoms

  • Diarrhea
  • Dizziness or light-headedness
  • Drowsiness
  • Fatigue or weakness
  • General malaise
  • Insomnia
  • Lack of appetite, nausea or vomiting
  • Needles and pins sensation
  • Nose bleed
  • Peripheral edema (swelling of hands, feet and face)
  • Persistent rapid pulse
  • Shortness of breath

Severe symptoms

Severe symptoms generally are life threatening and should be taken seriously. Serious symptom includes

  • Cerebral edema (swelling of brain)
  • Pulmonary edema (fluid in the lungs)


  • Avoiding alcohol consumption as far as possible especially at higher altitudes.
  • Ascending slowly is the best way to avoid altitude sickness.

Altitude acclimatization

Altitude acclimatization is the process where you adjust your body to the low level of oxygen by slowing ascending while trekking or staying a day or two at high altitude before ascending again. If you have noticed, most itinerary while trekking in Nepal reserve a day or two for rest and acclimatization.

Dealing with the worse case

No matter how  well you prepare, you have to prepare for the worse as well. Some people just don’t adjust well to higher altitude no matter how well build or fit they are. In such cases, one might suffer from altitude sickness and have to be rescued for high altitude to save his/her life. Rescue in Nepal while trekking is mostly done via Helicopter because the area you will be trekking are usually very remote and no road access. So, helicopter is the only way for rescue.

Such rescue operation becomes very expensive so we strongly recommend that you buy an insurance policy that supports helicopter rescue and medical treatment expenses. Some of the leading insurance company worldwide is listed below

  • Vanbreda International (Belgium)
  • Mondial Assistance Deutschland Gmbt (Germany)
  • International SOS (Singapore)
  • Inter Mutuelles Assistance (France)
  • Harel Insurance Company, Shiloah (Israel)
  • GMC Services (France)
  • Europe Assistant (France)
  • Euro – Centre Co. Ltd. (Thailand)
  • Bupa International (Denmark)
  • ADAC Ambulance Services (Germany)

Please be careful while trekking in higher altitude and make sure that you take your time while trekking. Make sure that you have properly acclimatized with the altitude and don’t push yourself too much while trekking. If possible don’t trek alone, always have a friend/trekking partner or trek through a certified trekking company in Nepal who will provided you will well trained and experienced guide for your trek.