Diamox (Acetazolamide) is a sulphur-based diuretic, which aids in acclimatisation to high altitude. It must NOT be taken by anyone with an allergy to sulphur drugs.
How does it work?
Diamox works by changing the ‘acid-based’ balance in your blood. As a result of this, your brain tells you to breathe more, and this increased ventilation (breathing) helps your body to acclimatise more rapidly to the decreased oxygen in the air available at altitude.
Are there any side effects?
The most common side effect is tingling in the hands and feet, especially for a few hours after taking the tablets. Occasionally people experience a mildly upset stomach, and, rarely, increased sensitivity to the sun. Because diamox is a diuretic it is not uncommon to become constipated after a few days use. Drinking plenty of fluids will help prevent this.
What is the dose?
125mg or half a tablet twice a day. You can take up to one tablet twice a day if needed.
When should I take Diamox?
Diamox can be used in two ways:
1. To help prevent Acute Mountain Sickness (A.M.S) as it is effective in 75% of individuals
2. To treat mild altitude sickness
As a preventative measure Diamox is best used on trips where you are rapidly ascending to high altitudes. On this type of trip you may not have enough time to acclimatise naturally and if you suffer from altitude sickness your enjoyment of the trip will be diminished.
Examples are: Climbing Mt Kilimanjaro or spending just a few days in the Andes of Peru or Bolivia. In these cases you should start taking Diamox the day before you ascend to altitude and continue until you have descended below 2800 meters.
Another option is to see how you feel, and commence Diamox only if you are unable to acclimatise easily (see ‘Altitude Sickness’ information sheet for symptoms).
The best treks are those that allow you to acclimatise slowly, for example, most treks in Nepal. It is advisable to follow the suggested acclimatisation guidelines but to have some Diamox as backup if required.
Remember, Diamox should NEVER be regarded as a substitute for IMMEDIATE descent if you or one of your group is suffering severe illness or worsening symptoms of A.M.S.
It can however be useful to start taking Diamox if you have persistent mild symptoms after 24 – 48 hours at a particular altitude. Only if your symptoms disappear after taking Diamox. can you safely continue your trek. You can then stay on the Diamox until you have returned to an altitude below that at which you got symptoms. If your symptoms don’t settle you should descend to a lower altitude.
It is important not to rely on Diamox as a substitute for descent if you are developing worsening symptoms of Acute Mountain Sickness