How Diamox plays a role in AMS
Diamox is the biggest topic of discussion because purists and non-purists have different view about acclimatization on a high altitude trek.
The purists say that using drugs to acclimatize like Diamox goes against the spirit of trekking or hiking. They stick to acclimatize naturally and ascend slowly with breaks – giving the body sufficient time to get used to the higher altitude.
But the non-purists think take Diamox to be on safer side rather than suffer from high altitude sickness. They feel being on a course of Acetazolamide (Diamox) would give them maximum chance of success on a high altitude trek. So they start the course of Diamox before going on high altitude trek.
Do you agree with Purists or do you think like non-purists?
Before getting the answer just have a look on what is Acute Mountains Sickness. It will help you to understand more about this.
When trekkers go above 8,000 feet, the atmospheric pressure starts to fall noticeably and to get oxygen with every breath become less so your blood doesn’t get proper oxygen. In this condition we need more oxygen we didn’t get so we started taking oxygen from mouth or we descent from that altitude. If you move to uphill then acute will increase and you will feel sleepy as well so be careful with acute mountain sickness.
But there is good news as well when you go up hill and your body has good adaptability of high altitude then your body will automatically acclimatize according to the oxygen. Your body builds up a ‘zone of tolerance’ – where it can function normally even with the decreased oxygen. This zone of tolerance moves up as your body acclimatizes to the higher altitudes. However, when the build-up of carbon dioxide is beyond your zone of tolerance your body reacts and you fall sick. This is AMS.
AMS is when along with headache you display the following symptoms:
Persistent Headache
Fatigue or Weakness
Nausea and vomiting
Dizzy and light headache
Loss of apetite
Difficulty sleeping
If somebody say he or she feels headache at the height of 11000 feet and the people around him or her say this is normal, it means they are not much aware about the symptoms of AMS. When you feel headache, just stop there and drink one liter of water and take a Disprin and watch for an hour because dehydration can be the cause of headache. If you feel you headache is still painful and constant then you are suffering from AMS. Without any second thought just descent to the altitude where you feel comfortable.
This condition allows using Diamox to prevent high altitude sickness. The question is really not whether to use Diamox or not. Your decision is the main factor because duration always matter. If you are going on 6 days trek and passing 14000 feet altitude then your body will not get the time to acclimatize properly. In this condition start the course of Diamox before you start a trek. But on the other hand if you planned you trip properly and reaching the place before a day or 2 day to give time to your body to get acclimatized then you don’t need Diamox.
In general, your body needs 24-48 hours to get acclimatized if you are moving above 10000 feet before moving up from. Modern day trekking, unfortunately, does not allow us this 10000 feet. We always prefer to reach by the afternoon and then we start trekking in the next morning so we can get proper time to acclimatize.
If you are not getting at least 24 hours to get acclimatize then it is better to start the course of acclimatize.
If somebody has done several high altitude trek that person can also suffers from AMS. There is no significant effect of age, gender, physical fitness or previous high altitude trek experience.
What does Acetazolamide (Diamox) do?
90% of the blood’s carbon dioxide exists in a chemical called bicarbonate. This carbon dioxide after travelling through your blood is exhaled by your lungs. Diamox forces the kidneys to excrete bicarbonate from your body (when you urinate).
Your body doesn’t like that. It needs the bicarbonate to exhale carbon dioxide through your lungs.
When Diamox forces you to excrete biocarbonates, your blood, which is used to a certain level of acidity, becomes more acidic. When the blood gets acidic it believes that it has more carbon dioxide in it. So the body gets rid of this excess carbon dioxide in a simple way. It starts to breathe deeper and faster, getting rid of the carbon dioxide, and also taking in more oxygen.
In effect, the increased oxygen speeds up the acclimatization process. It also greatly reduces you of any symptoms of altitude sickness. Which is why Diamox works best when you start on it a day or two before you get to high altitudes.
In a recent conversation with Dr Shubit Chabbra, the leading expert in India on high altitude hypoxia, he told me that the best step that a trekker could take to prevent any high altitude sickness was to be on a course of Diamox prior to the start of the trek. He said more lives could be saved and more treks successful if the trekkers were on a course of Diamox than without.
Remember, Diamox accelerates acclimatization. It does not cure anything. If you have headache with any of the above symptoms, even after taking Diamox, it means your acclimatization is not complete and you must descend. Under no circumstances should you climb higher if your symptoms still persists.
Diamox dosage
Start on a dosage of 125 mg every 12 hours 2 days prior to your trek (or when you arrive at Delhi). Increase it to 250 mg every 12 hours from the day you get to the base camp and continue until you complete the trek.
Side effects of Diamox
While Diamox is harmless for most people, please check with your doctor whether you are allergic to sulphides. Also check with your doctor if you have high/low blood pressure or diabetes.
Diamox is a sulfa-based drug. So if you’re allergic to sulphides, avoid Diamox.
We used to use Diamox only in emergencies – however, now we have reviewed our stand and we suggest participants start on Diamox two days before they start the trek. The chances of a successful and stress free trek is much higher if participants start on a course of Diamox on arrival at Delhi.
Altitude training
While Diamox reduces your chances of getting any high altitude sickness, it is important to prepare your lungs to be ready to work with less oxygen. The best way to do that is to prepare for a trek. A good altitude training program must include cardio-vascular, strength and flexibility training. I would recommend a run of half an hour and covering a distance of 4.5 km as good preparatory altitude training.
