Altitude Sickness What it is and How to Avoid It

The colloquially called mountain sickness or altitude sickness is the lack of adaptation of the body to the lack of oxygen (hypoxia) at altitude. It is a very common mistake to think that the amount or concentration of atmospheric oxygen decreases with altitude. In reality, the oxygen concentration is always the same (approximately 21%) regardless of altitude. What happens is that, as we ascend, there is a progressive decrease in atmospheric pressure and also in the partial pressure of oxygen in the air that we inspire.


For some time now, the mountain teams have experienced a great improvement and the mountaineers are becoming better prepared. There are more routes to climb the more complicated mountains, although in the high mountains there is still a high rate of accidents on the climbs.

The incidence of altitude sickness varies greatly from one person to another because some endure fast ascents better than others. It appears after 6 or 10 o'clock, it is more frequent in children under fifty years of age and in subjects who usually reside at less than 900 m of altitude. Fitness or physical preparation - excellent as they are, does not prevent it - as it can affect even the most experienced athlete.

Susceptibility to altitude sickness is known to be inversely proportional to the age of the subject, probably due to the maturity of the nervous system. The use of drugs to prevent it is also not recommended, but rather to progressively adapt to altitude hypoxia through an acclimatization process.

Other factors that influence the appearance of poor altitude are the speed of ascent (the faster, the greater the probability of appearance), the length of stay at a certain height and exercise at high altitude. In addition, it is very important to keep in mind that, despite scrupulously following an acclimatization calendar, altitude sickness can occur at any time.

Altitude sickness symptoms

Mountain sickness can begin to be felt from 2,500-3,000 meters above sea level in sensitive people it can appear even at a lower altitude. The mildest symptoms are difficulty sleeping, dizziness or vertigo, fatigue, headache, loss of appetite, nausea or vomiting, tachycardia, and respiratory distress.

For practical purposes (in the mountains, above 2,500 m), the appearance of any of the symptoms described that cannot be explained for other reasons should be considered as altitude sickness. It is necessary to stop ascending and, if the symptoms do not improve, go down to lose altitude as soon as possible, at least to the level where there were no symptoms.

As for the severe symptoms, it includes the bluish coloration of the skin (cyanosis), stiffness or congestion of the chest, confusion, cough, decreased state of consciousness, paleness, absolute inability to walk and respiratory distress. If no solution is given, it will evolve to more severe complications, so treatment must be urgently put in.

How to deal with altitude sickness

The first rule that must be applied to any problem derived from height is the descent to lower levels. The second measure is to administer oxygen through a mask. The practice of these two elementary measures is more than enough to solve most of the cases. If not resolved, use measures strictly reserved for medical personnel should not be used, as their misuse or incorrect use is potentially dangerous, and even fatal.

Tips to avoid altitude sickness

The best recommendation is to do a gradual climb. The first and most important thing is to climb relatively slowly, performing adequate acclimatization periods

Rest and hydration

In case of problems, it is essential to descend to a lower level than the one acclimatized and rest for 24 or 48 hours before resuming the ascent. If the symptoms are severe, start the descent immediately, always accompanied. In these situations it is necessary to drink a lot of liquid (at least 3 or 4 liters a day), avoid drinking alcohol and follow a hyperglucidic diet, rich in sugars and carbohydrates.

Profiles with risk

Those with heart and lung diseases are more at risk even if they have been successfully treated. Pregnant women, children, people with high blood pressure, a tendency to sleep apnea and those who have had altitude sickness before.

Prior recognition is vital

Despite the fact that altitude sickness does not depend on the physical form of the person and can affect even the most experienced athletes, what is certain is that, as in any other athlete, a comprehensive sports medical examination will help us detect a series of pathologies that predispose and increase the severity of altitude sickness. Among them are chronic heart and lung diseases such as angina, chronic bronchitis, emphysema, and some people with severe asthma, anemia, including sickle cell anemia (low blood hemoglobin content).

Also untreated blood clotting disorders or those patients with a history of thrombosis (clots). This recognition will indicate in turn how we should act, what measures to take into account in terms of preparation and diet and advice for training and for sports in general.

Source: fundacionio

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