• The best way to prevent getting altitude sickness is to travel to altitudes above 2,500m slowly.

It usually takes a few days for your body to get used to a change in altitude. You should also:

• • Avoid flying directly to areas of high altitude, if possible
  • Take 2 to 3 days to get used to high altitudes before going above 2,500m
  • Make sure you’re drinking enough water
  • Avoid smoking and alcohol
  • Avoid strenuous exercise for the first 24 hours
  • Eat a light but high-calorie diet

• If you know you think you may be working at altitudes above 2000m then you should speak to your doctor for medical advice and it should be considered in the Travel Risk Assessment.

• If you think you have altitude sickness:
  • stop and rest where you are
  • do not go any higher for at least 24 to 48 hours
  • make sure you’re drinking enough water
  • do not smoke, drink alcohol, or exercise
  • Tell your travel companions how you feel, even if your symptoms are mild – there’s a danger your judgement may not be clear.

If you do not feel any better after 24 hours, go down by at least 500m (about 1,600 feet).

After 2 to 3 days, your body should have adjusted to the altitude and your symptoms should disappear.

See a doctor if your symptoms do not improve or get worse.

• If the symptoms of altitude sickness are ignored, they can lead to life-threatening conditions affecting the brain or lungs.

• High altitude cerebral oedema (HACE) is swelling of the brain caused by a lack of oxygen.

Symptoms of HACE include:

• headache
• weakness
• feeling and being sick
• loss of coordination
• feeling confused
• hallucinations (seeing and hearing things that are not there)

A person with HACE will often not realise they’re ill. They may insist they’re OK and want to be left alone.

HACE can develop quickly over a few hours. It can be fatal if it’s not treated immediately.

Treating HACE:

• move down to a lower altitude immediately
• take dexamethasone
• give bottled oxygen, if available

You should go to hospital as soon as possible for follow-up treatment.

• High altitude pulmonary oedema (HAPE) is a build-up of fluid in the lungs.

Symptoms of HAPE:

• blue tinge to the skin or lips (cyanosis)
• breathing difficulties, even when resting
• tightness in the chest
• a persistent cough, bringing up pink or white frothy liquid (sputum)
• tiredness and weakness

The symptoms of HAPE can start to appear a few days after arrival at high altitude. It can be fatal if it’s not treated immediately.

Treating HAPE:

• move down to a lower altitude immediately
• give bottled oxygen, if available

You should go to hospital as soon as possible for follow-up treatment.

If you’ve had HAPE, you can register with the International HAPE Database to help develop new treatments for the condition.