Altitude Sickness

Symptoms of altitude sickness

Symptoms of altitude sickness usually develop between 6 and 24 hours after reaching altitudes more than 3,000m (9,842 feet) above sea level.

Symptoms are similar to those of a bad hangover.

They include:

• headache
• nausea and vomiting
• dizziness
• tiredness
• loss of appetite
• shortness of breath

The symptoms are usually worse at night.

It's not possible to get altitude sickness in the UK because the highest mountain, Ben Nevis in Scotland, is only 1,345m.

Medication

Consider travelling with these medicines for altitude sickness:

• acetazolamide to prevent and treat high altitude sickness
• ibuprofen and paracetamol for headaches
• anti-sickness medication, like promethazine, for nausea

Preventing altitude sickness

The best way to prevent altitude sickness is to travel to altitudes above 3,000m slowly.

It usually takes a few days for the body to get used to a change in altitude.

You should also:

• avoid flying directly to areas of high altitude, if possible
• take 2-3 days to get used to high altitudes before going above 3,000m
• avoid climbing more than 300-500m a day
• have a rest day every 600-900m you go up, or every 3-4 days
• make sure you're drinking enough water
• avoid alcohol
• avoid strenuous exercise for the first 24 hours
• eat a light but high calorie diet
• avoid smoking

Acetazolamide, available from a travel clinic and, in some areas, your GP, can help prevent symptoms. It's thought to help you adjust more quickly to high altitudes.

You should begin taking the medication 1-2 days before you start to go up in altitude and continue to take it while going up.

If using acetazolamide, you should still go up gradually and follow the general prevention advice.

If you get symptoms of altitude sickness while taking acetazolamide, you should rest or go down until you feel better before going up again.

Treating altitude sickness

If you think you have altitude sickness:

• stop and rest where you are
• don't go any higher for at least 24-48 hours
• if you have a headache, take ibuprofen or paracetamol
• if you feel sick, take an anti-sickness medication, like promethazine
• make sure you're drinking enough water
• avoid alcohol
• don't smoke
• avoid exercise

Acetazolamide can be used to reduce the severity of your symptoms, but it won't completely hide them.

Tell your travel companions how you feel, even if your symptoms are mild – there's a danger your judgement can become clouded.

You can continue going up with care once you feel fully recovered.

If you don't feel any better after 24 hours, you should go down by at least 500m (about 1,600 feet).

Don't attempt to climb again until your symptoms have completely disappeared.

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

See a doctor if your symptoms don't improve or get worse.