Andes Altitude Sickness – How To Avoid It!
All treks in the Andes involve going to ‘high altitude‘, and therefore come with obvious altitude sickness risks. It is important that you understand these risks so that you can take the best preventative actions, as well as be well-informed on how to deal with altitude sickness symptoms, and it’s severe variants – High Altitude Cerebral Edema (HACE) and High Altitude Pulmonary Edema (HAPE) – both are very rare conditions on Andes hikes.
In this detailed article on Andes altitude sickness I have provided general information on the process of acclimatisation, an overview on altitude sickness, HACE and HAPE, as well as provided details on preventative medications like Diamox and natural remedies like coca tea, Muña tea(wild meant herb from the andes) and water.
Disclaimer: The information on this page is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes. The information is not intended to be patient education, does not create any patient-physician relationship, and should not be used as a substitute for professional diagnosis and treatment. Research in this area is always progressing which may mean some of this information is out of date. It is your responsibility to seek the latest information should you be going to high altitude.
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Altitude Sickness - A Guide
Acclimatisation
Acclimatisation refers to the process by which the body becomes accustomed to lower levels of oxygen, and is only achieved by spending time at various levels of altitude before progressing higher. In mountaineering parlance, there are three main levels of altitude:
- High altitude describes the altitude zone between 2,500m and 3,500mVery high altitude is between 3,500m and 5,500m
- Extreme altitude is above 5,500m.
There are other zones above extreme altitude, like over 5,800m like Ausangate, most people can ascend from sea level to 2,400m without experiencing altitude sickness symptoms, but beyond this height changes in oxygen and pressure levels start having an impact on people’s physiology.
What makes treks to the Andes tough, and potentially dangerous, is the speed at which you arrive at high altitude. Most, if not all visitors to Machu Picchu, arrive by flying into Cusco which sits at 3,400m – on the boundary of the high and very high altitude zone.
Cusco city - Plaza de Armas
Acclimatising On Your Hikes
How does acclimatisation apply to your hikes on the Andes?
So, as I mentioned above, Cusco is already at high altitude and generally above most people’s acclimatisation line, for trekkers, the best solution in my opinion, is to stay in Cusco for at least two days to starve off mild altitude sickness symptoms and acclimatise (most tour operators include a two day acclimatisation period in Cusco as part of their tour package).
All trails in the Andes involve going over high passes (over 4,500m), so acclimatising early, despite at a relatively high altitude, is worthwhile, alternatively, if you are just visiting Machu Picchu (2,430m) by train, it is possible to fly into Cusco (3,400m) and then descend immediately into the Sacred Valley (1-2 hour bus/car ride) to the towns of Urubamba (2,800m) or Ollantaytambo (2,792m) where it is easier to start the acclimatisation process.
Resting here for a day or two before proceeding to Machu Picchu by train, which departs from Ollantaytambo, can help lower the probability of experiencing altitude sickness. The absolute ideal scenario would be to fly into Cusco and then immediately drive to the Sacred Valley to rest for a couple of days. Then return to Cusco to rest for a few days, and then begin your trek. Most people don’t have the time or inclination to do this
Altitude Sickness Symptoms
The altitude sickness, is a pathological condition caused by going to high altitudes, too fast.
Most people start experiencing altitude sickness at 3,000m, some can experience altitude sickness symptoms as low as 2,400m. Unfortunately there is no correlation between age, fitness, health and gender that can help predict one’s susceptibility to altitude sickness, all I know for sure is that ascending more than 500m a day from 2,400m increases the probability of altitude sickness, as does exercising at high altitude and dehydration.
Altitude sickness symptoms include headache, nausea, vomiting and lightheadedness. The different levels of altitude sickness have different symptoms.
Symptoms of mild, short-term altitude sickness also include dizziness, fatigue, shortness of breath, loss of appetite, sleep problems and a general loss of energy and it can be separated into three levels – mild, moderate and severe. One typically moves from mild symptoms to more acute and extreme symptoms as the condition worsens.
Mild altitude sickness symptoms include: fatigue, headaches, nausea and lost appetite, dizziness, disturbed sleep and shortness of breath. Mild altitude sickness symptoms typically present between 12-24 hours after arriving at altitude and are common for visitors to Cusco. Remaining for 24-48 hours at the altitude at which mild altitude sickness occurs usually resolves symptoms. Once symptoms have passed at the altitude they started, you can assume you have acclimatised to that altitude.
Signs that you are suffering moderate altitude sickness include very bad headaches that aren’t relieved with medication (think the worst migraine you have ever had), awful nausea, sometimes resulting in vomiting, extreme fatigue and weakness, shortness of breath, and a feeling of decreased coordination (known as ataxia).
Most people suffering from moderate altitude sickness symptoms can still walk but ascent under these conditions will almost certainly result in worsening of the condition. Descent is the only cure for this condition and time should not be wasted in getting someone down to the altitude at which the symptoms were not present. Once the symptoms have subsided it is possible to continue ascending.
Severe altitude sickness symptoms include an inability to walk, extreme shortness of breath, loss of cognitive capacities (ability to think straight), hallucinations and fluid build on the lungs. HACE and HAPE are commonly associated with severe altitude sickness and occur when fluid leaks into the brain or through the capillary walls into the lungs, respectively. Ascent under these conditions is extremely dangerous and potentially fatal. Immediate decent is required.
High Altitude Cerebral Edema (HACE) – High Altitude Pulmonary Edema (HAPE)
Medications & Natural Remedies
Diamox
Acetazolamide, known by the brand name Diamox, is a drug that has been proved effective in mitigating the effects of altitude sickness. It is a prophylactic (preventative medication), not a cure. In other words it promotes faster acclimatisation and helps prevent the onset of altitude sickness, but does not cure it. In some countries the drug requires a prescription, but in general it can be bought over the counter. One should however consult their doctor before using it. Pregnant women or people with kidney and liver issues should not take the drug, the side effects include increased urination; numbness and tingling in fingertips, toes and nose; taste alterations; and nausea, vomiting and drowsiness.
The last three side effects can be confused with altitude sickness so it is recommended that one takes a short dose of Diamox a few weeks before departing for your treks to test any side effects, Diamox is generally sold in 250g t
ablet format. Trekkers typically take 125g in the morning and the remaining 125g in the evening, starting one day before arriving in Cusco and finishing on the day one leave’s Cusco.
I believe it is worthwhile taking Diamox as a preventative measure but rec
ommend consulting your doctor before you do
Coca Leaves
Coca is a plant that grows naturally in Peru and features prominently in Andean culture for it’s medicinal and religious purpose. A pharmacologically active ingredient in the coca plant, called the coca alkaloid accounts for about 0.8% of the fresh leaf and in its refined form makes cocaine. Drinking coca tea or chewing the leaves do not however produce the same effects as cocaine.
When chewed, coca can act as a mild stimulant and has been shown to repress hunger, fatigue, thirst and pain. Traditionally, Andean people use the coca leaf for a number of medicinal, nutritional and religious purposes, one traditional use is in the prevention of altitude sickness. Locals either chew the leaves or drink coca tea, and encourage tourists to do the same as a preventative measure.
Muña tea ( Wild mint tea)
If you are on medication that you can’t drink coca tea with, or if it is too late in the day and you need something to help with altitude sickness, Muña tea is an excellent alternative. Cusco hotels and restaurants also provide this. This is an antiseptic, mint tea, which also helps with stomach issues
Staying hydrated is also important in preventing altitude sickness. Drink water regularly during your climb The IAM recommends drinking an extra 1-1.5 liters of water daily at high–altitude, for a total of 3-4 liters. Ideally, those 3-4 liters would contain 2-300 grams of carbohydrates. Supplementing electrolytes is important for any high-output activity, but it becomes crucial at higher altitudes as well