I have been meaning to write something on Altitude Sickness or Acute Mountain Sickness (AMS) for such a long time because I spent a while trekking and living at high altitudes in Nepal, Bolivia, and Peru. During that time, I had some experience of AMS and met many others who suffered from varying degrees of it.
What is Acute Mountain Sickness (AMS) and its causes?
From about 2,400m above sea level upwards, you begin to put your body to the test. The change in conditions has a big impact on your body and it has to adapt to cope with low levels of oxygen in your blood that, at sea level, would have you hospitalised, given oxygen, and closely monitored. AMS occurs when our body doesn’t adapt well to having lower levels of oxygen due to a higher altitude.
A team of researchers may have found a way to predict who is predisposed to getting AMS with a quick and simple low-cost test. It needs to be confirmed with a larger study, but we may soon have a reliable way of finding out if we are susceptible to suffering from AMS. Until then, you can never really know if your body will adapt to being, let alone trekking, at increasingly higher altitudes because anyone can potentially suffer from AMS. It is not related to age, physical fitness, or gender. I came across a few men on my trek to Everest Base Camp, who thought they were invincible because they were young and fit, only to see them days later at a lower alttitude recovering from the symptoms of AMS. And, just because you were once fine at a high altitude doesn’t mean you will never suffer with AMS although, according to A.D.A.M. Medical Encyclopedia, you are at a higher risk of acute mountain sickness if you have suffered with it before.
Symptoms of AMS
Mild symptoms include being short of breath on exertion, headache, tiredness, nausea and vomiting, difficulty sleeping, and a rapid heart rate.
More severe symptoms such as chest tightness, cyanosis, confusion, coughing up blood etc. can lead to pulmonary oedema in the brain and/or lungs, which are the more serious conditions of High Altitude Cerebral Oedema and High Altitude Pulmonary Oedema.
Obviously, you need to be cautious if you or another person experiences any symptoms, but especially the more severe symptoms because it can be fatal. I’m not trying to scare you but just to make a point; last year, a British man, who was in the town of Aguas Calientes on his way to see Machu Picchu, collapsed and died after suffering with breathlessness (I assume at rest) for a few days. His death was linked to high altitude.
Prevention and treatment
There are traditional remedies that, although might not be clinically proven, are thought to help prevent and lessen the effects of AMS. In Nepal, it’s garlic. I had a lot of garlic soup as I trekked to Everest Base Camp. I have no idea if it made any difference but, as there are no side effects, it’s worth trying.
In Bolivia and Peru, it is Coca tea. I was at a high altitude for weeks while I was in these countries and I drank a fair bit of coca tea. I had no symptoms of AMS at all and even managed to Salsa dance while I was in Cusco although, understandably, I got out of breath a lot quicker and needed to drink more water than normal.
It’s important to acclimatise to the increase in altitude. If you’re trekking, as CIWEC Clinic’s website states, a ‘sensible itinerary’ is important. By that they mean, not climbing more than 300m a day once you reach 3000m or resting for 2 days if you climb 600m in one day. This is what I did. The most important thing is time. If you and/or your guide has only a certain amount of time for the trip, the pressure is on to keep ascending, even if you need more time. The rate at which you climb differs from person to person, so what might be ascending too quickly for one person will be fine for another. It’s a very individual thing. That makes it difficult when trekking in a group and treks designed to last a certain number of days. The main thing is to go with what your body is telling you. If you need to stop for longer, stop. At the end of the day, your health is more important than getting to Everest Base Camp or whatever goal you have in mind. Your guide, as mine did, might have the best intentions to get you there but if your body isn’t adapting to the change in altitude, you either need more time to get there or have a more achievable goal. I met plenty of people who had to descend and try again and some who never reached Everest Base Camp because their bodies couldn’t adapt to the altitude in the time they had to do it.
Diagnosing and treating AMS early is obviously the best solution. Descending to a lower altitude is important to do as quickly as possible. I saw how well that can work as I was making my descent. A British girl was carried in by her guide to the guesthouse I was stopped at. She wasn’t really responding and couldn’t eat or drink anything. After a short while, the guide picked her up again and headed down even further. It was particularly tense because he had to cross a fast-flowing river where the water level had risen due to the rainfall and the stepping stones were really far apart. I had refused to go across that afternoon because I didn’t think it was safe, but this guide obviously felt he had no option. It was scary to watch as he carried this girl across the river but, after a few nail-biting minutes, he had crossed to the other side. When we met them the next day, the girl was responsive, chatting, and eating. Due to her guide’s quick action and courage, she made a remarkably quick recovery.
There are two drugs that, according to the NHS website, can be used to prevent AMS: Diamox (Acetazolamide) and Dexmethasone. On the CIWEC Clinic’s website, they suggest only the former, Diamox, as a way of preventing and treating mild forms of AMS. It is worth reading about the various ways of preventing and treating AMS and discussing it with your doctor in advance, if you can. When you are mid-trek it is more tricky, although there is a health post on the way to Everest Base Camp in Namche Bazaar.
As he saying goes: To be forewarned is forearmed, which means if you know about something, you can prepare for it. I hadn’t thought any of this through in advance because I was under the impression that the season for trekking to Everest Base Camp was over. When I realised it wasn’t, on a whim, I booked and left for the trek the next day. What I hadn’t banked on was getting a head cold at the start of the trek. Having a head cold and trekking at increasingly higher altitudes isn’t a good combo, believe me! I made use of the health post on Day 2 of my trek, having developed a headache. The nurse gave me the all-clear to continue. Because I was feeling awful and Paracetamol didn’t seem to be helping, my guide offered me Diamox. I was wary of taking something I knew very little about but, in the end, I took one tablet because I felt so awful, which helped. The thing is, there is always the risk of side effects when you take tablets and these are no exception. The next morning, as we set off, I started to get pins and needles in my hands and feet. When I took off my gloves, I could see the veins in my hands pulsating. That was a little scary, so I was very wary about taking any more tablets. A week into the trek, still with my head cold, I awoke from an afternoon nap, gasping for breath. This was probably due to the combination of a blocked nose and the low level of oxygen. One of the guides, staying at the same guesthouse, suggested Sancho. This is a traditional Himalayan remedy – a blend of pure natural essential oils. The combination of inhaling a few drops of Sancho on a tissue, taking half a tablet of Diamox a day, and garlic soup worked for me and I didn’t have any side effects from the smaller dose of Diamox. I felt a whole lot better and made it to Everest Base Camp and up to Kala Patthar, which was the highest point at approximately 5,545m above sea level. That’s me having a celebratory Mars Bar at the top, so I must have been feeling better!
The moral of the story is to learn from my experience and, if there is the slightest chance of trekking or living at high altitudes on your travels, find out as much information as you can about AMS, so you know the symptoms and what to do should you or someone else become symptomatic. Also, trekking at high altitudes with a head cold isn’t advisable!
For lots more really useful information about AMS, take a look at the CIWEC Clinic’s website and visit your doctor for information and advice before you leave for your travels.
Have your say
What was your experience of being at a high altitude? Did you suffer from any symptoms of AMS? Do you have any other useful information or advice about AMS?