Climbing at altitude means that the air becomes thinner and it becomes more difficult to breathe. Whilst many climbers are acclimatised to this, others can experience various degrees of altitude sickness. Prevention is always much more preferable to cure, however, and whilst there are certain ways of treating it, the best thing is to be able to recognise the symptoms and to take necessary precautions.
A moderate to severe headache as you ascend a climb is a sure sign that you may be developing altitude sickness, although a headache can also be an indicator of dehydration so the only way of determining the problem is that if you’re sure you’ve kept yourself well hydrated, then it’s a signal that you could have altitude sickness. Other symptoms include nausea, vomiting, dizziness, fatigue and pins and needles.
Whenever you climb, you should always begin a climb below 3,000 metres as it’s above this height that you can start to experience altitude sickness and if you start your climb well below that height, this gives your body more time to get acclimatised. Keep well hydrated taking in between 4 to 6 litres of water a day. If your urine is clear or just pale yellow-coloured, it’s a sign that you’re taking in enough fluids. Once you get above 3,000 metres, take things a little more slowly at first to allow your body to adjust as overexertion will exacerbate the onset of altitude sickness. Avoid things like alcohol, tobacco and any depressant medication or sleeping tablets as they will decrease your level of respiration. As for food, make sure your diet is high in calories.
If you start to experience any of the symptoms outlined above, do not climb any higher until they show signs of decreasing and if they increase, then you need to move down and continue to move down. It’s also important to remember that the different people in your climbing party will become acclimatised to altitude at different rates so it’s crucial that you all keep an eye out on each other and stop climbing if just one member of the party is showing signs of suffering from altitude sickness. Acetazolamide (Diamox) has also been popular in both the prevention and treatment of altitude sickness by increasing the amount of alkali which is excreted in your urine. This in turn makes your blood more acidic which helps your ventilation which is at the heart of getting acclimatised to altitude.
Apart from Diamox, the only real ‘treatment’ is to either descend or wait where you are until you have naturally become acclimatised. Even with Diamox and other similar medications, you’re only really reducing the symptoms and, in doing so, this could be concealing other health problems you might be experiencing. If a person is suffering from severe altitude sickness which immobilises them, there is a device called a Gamow bag and you’d put the casualty into this bag. It’s basically a plastic portable sealed pressure bag which is operated with a foot pump. It works by creating an atmosphere inside it which is the equivalent of being around 3,000 to 5,000 feet lower than you actually are. This means that after spending approximately 2 hours inside the bag, the casualty’s body chemistry will adjust so that they will perceive themselves to be much lower than they are in reality. This then gives them enough time to descend even further to an even lower altitude and will enable them to acclimatise further.