The short answer
Ascend gradually, rest, drink water and descend if symptoms worsen. Headache, nausea and dizziness above about 2,500 m are warning signs that your body is struggling to adjust.
Altitude sickness can affect anyone, whatever their fitness. The best protection is a slow, well-planned itinerary with acclimatisation days, plus the honesty to tell your guide when you feel unwell.
Key facts
- Warning
- Headache, nausea
- Rule
- Go slowly
- Action
- Descend if worse
- Meds
- Ask a doctor
How it works
- Plan acclimatisationChoose an itinerary with rest days and gentle height gain, not the fastest schedule.
- Walk slowlyKeep a pace where you can still talk. Slow is steady at height.
- Drink waterAim for regular sips through the day and pass pale urine.
- Avoid alcoholAlcohol and sleeping pills make acclimatisation harder.
- Descend if symptoms worsenGo down early if headaches or breathlessness increase, and tell your guide at once.
Reading the warning signs
Mild symptoms include a headache, poor sleep, loss of appetite and slight tiredness. These are common and usually settle with rest and fluids, but they are a signal to stop climbing and let your body catch up. Do not go higher until the symptoms have gone.
More serious signs include a headache that keeps getting worse, vomiting, confusion, a wobbly walk, breathlessness at rest or a wet-sounding cough. These need immediate descent and medical help. Never leave someone with these signs alone.
How to give your body time
Above about 3,000 m, try to sleep no more than a few hundred metres higher each night, and add a rest day every few days. Walk slowly, drink water through the day, and avoid alcohol and sleeping pills. A well-planned itinerary builds in these rest days for you.
Fitness helps your trek but does not stop altitude illness. Talk to your doctor before you go if you have a heart, lung or blood condition, and ask about medicines such as acetazolamide, which are prescribed by a doctor and are not a replacement for a slow ascent. See the high-altitude care guide for more.
Insider tip
Add rest days when you cross 3,000 m.
Avoid this
Do not ignore symptoms or ascend when unwell.
Related questions
Who gets altitude sickness?
Anyone can, regardless of age or fitness. Past trouble at altitude increases the chance of it happening again.
Can I take medication?
Some doctors prescribe a medicine to help prevention. It does not replace a slow ascent, so ask your doctor well before you travel.
At what height does it start?
Symptoms can begin around 2,500 m, though many people feel fine until higher.
Does the Muktinath yatra need care?
Yes. Muktinath is high, so plan rest, water and slow walking, and ask your doctor if you have heart or lung conditions.
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