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Altitude sickness

Altitude sickness is a highly unpleasant experience and occurs when you reach about 2500 metres. It occurs because the air is thinner with less oxygen available to you.

Your body will adjust to this by increasing your breathing rate and also your heart starts to work harder. Most people can acclimatise efficiently at heights of 2000-3000 metres within a couple of days but if you are planning on going higher you should allow up to 3 weeks.

You are more likely to get altitude sickness the faster you elevate. For example if you fly direct into La Paz, Bolivia (3000m) or drive up to Lhasa, Tibet (3600m) you are more likely to experience symptoms than if you were to trek to altitude. Overexerting yourself before you have become accustomed to the height will also increase your risk.

Altitude sickness symptoms include:

More severe symptoms include:

These symptoms can be life-threatening so DESCEND IMMEDIATELY:


Altitude sickness is not dependant on your age or even your level of fitness; anybody can experience the effects.

The most important factor in reducing the risk of AMS (Acute Mountain Sickness) is to ascend slowly, allowing time to acclimatise. Once symptoms are present you must DESCEND IMMEDIATELY.

It is tempting to rush into things when you arrive in countries at altitude but wait a couple of days before doing any strenuous activity or ascending further. If you are travelling with someone else keep an eye on each other for signs of trouble.


Even if you are only experiencing mild symptoms you should start your descent immediately as they will only get worse. NEVER keep climbing.

Seek medical advice if you have serious symptoms

Keep hydrated

Use painkillers or an anti-inflammatory

Rest for at least 2 days at lower altitude

Remember to get your travel insurance.