If you have very mild altitude sickness, continue to climb but make sure you do so gradually and at a steady rate.
Tell the people you are travelling with how you feel, even if your symptoms are mild. If your symptoms are slightly more severe, stay at your current altitude to let your body adjust. Also:
- do not exercise
- drink plenty of fluid (but not alcohol)
- do not smoke
- rest until you feel better
Descending to a lower altitude
If you have more severe symptoms of altitude sickness, or mild symptoms that do not go away over 24-48 hours, the best thing to do is descend to a lower altitude.
Going down by 300m (1,000 feet) will improve the symptoms of moderate altitude sickness and spending 24 hours at this lower altitude should significantly improve symptoms.
Remain at this altitude until your symptoms have completely disappeared. After two to three days, your body will have become acclimatised and your symptoms should have disappeared. At this point, you can start going up again.
If you have severe altitude sickness, descend immediately by as much as possible and by at least 600m (2,000 feet). You must descend as soon as possible because death can occur if altitude sickness is not treated quickly. If your symptoms do not significantly improve at the lower altitude, continue to descend until they do.
Bottled oxygen can be given to improve severe breathing problems caused by altitude sickness.
Medication
Painkillers
Painkillers, such as paracetamol or ibuprofen, can be used to treat mild headaches that are caused by altitude sickness.
Acetazolamide
Acetazolamide (Diamox) can help reduce the severity of the symptoms, and can also be used to help prevent altitude sickness occurring.
One of the effects of altitude sickness is that it changes the chemical balance of your blood. Acetazolamide helps correct this chemical imbalance.
Breathing more rapidly also enables you to take on board more oxygen, which helps to minimise symptoms such as headache, nausea and dizziness. This can be particularly helpful at night.
As acetazolamide is an unlicensed, prescription-only medication, you should consult your GP before taking it. There are a number of minor side effects associated with acetazolamide including:
- numbness or tingling of the face, fingers or toes
- excessive urination
- blurred vision (although this is rare)
Dexamethasone
Dexamethasone can be very useful for treating severe complications of altitude sickness, such as high altitude cerebral oedema.
Dexamethasone is a strong steroid that reduces swelling of the brain. It is usually taken in 4mg doses three times a day. Symptoms usually start to improve within about six hours.
Dexamethasone is particularly useful for ‘buying time’ until it is safe to make a descent. For example, it can be used during the night to relieve symptoms, when making a descent is not possible or may be dangerous.
Dexamethasone is effective in treating people with altitude sickness. If you are going on a climbing or trekking expedition, it is a good idea to take it with you for use in emergencies.
However, dexamethasone can cause side effects, such as:
- stomach upset
- euphoria (a state of excitement or elation)
- depression
As with acetazolamide, you should consult your GP before taking dexamethasone.
Nifedipine
Nifedipine is often used to treat high blood pressure. It can be useful in treating complications of altitude sickness, such as high altitude pulmonary oedema.
Nifedipine decreases the narrowing of the artery supplying blood to the lungs, helping to reduce chest tightness and ease breathing.
The recommended dosage of nifedipine is 20mg taken at six- to eight-hour intervals. Nifedipine can cause a sudden drop in blood pressure, so if you take it, do not get up too quickly from a lying or sitting position.
