Altitude Sickness
It is important to avoid the effects of high altitude travel because they can can be life threatening. Altitude sickness occurs in some people from as low as 2500 metres above sea level. The symptoms can be similar to hypothermia and can include headaches, vomiting, and shivering. I have ventured above 4000 metres in India, Nepal, Tibet, Tajikistan, Ecuador, Bolivia, and Peru. And, I have suffered altitude sickness (with the symptoms mentioned above) in all those countries, except Nepal and Peru where I had plenty of time to acclimatise.
Prevention for altitude sickness?
The experience, sights and sensation of travelling at high altitude in far flung parts of the World is magical. Usually, I suffer from altitude sickness (AMS) above 4000 metres, and so I always try to prepare to combat it. Different people react in different ways to altitude. My experience is that it has little to do with age, gender or fitness level.
Garlic, used in dishes and as a soup, is popular as a prevention for altitude sickness in the Himalayas. In the Andes, many people chew or consume coca leaves. A month before embarking on a high altitude journey, I begin taking the Gingko biloba root and continue taking it during my time at high altitude (see an example of scientific evidence for its use). There are also prescription medicines which you can take to prevent AMS.
However, the reason I was comfortable and unaffected above 5000 metres in Peru was because I had acclimatised over the previous month at altitudes above 3800 metres. When you are above 3000 metres, the ideal is not to sleep at more than 300 metres higher than the previous day, and if possible sleep at a lower altitude than you have ascended during the day. Make sure the clothes you are wearing are breathable – after removing my nylon raincoat in Kashmir, at 4500 metres, it was as if my body came back to life again!
Where symptoms of altitude sickness are severe, the best solution is to descend as soon as possible. It is not to be underestimated; people die every year from altitude sickness.