Altitude sickness is one of the most irritating problems of traveling to the high altitudes of the Tibetan plateau. For many people, arriving in Lhasa often means feeling the symptoms of altitude sickness, from the mildest symptom of a headache to nausea, dizziness, and sleepless nights that can happen.
Altitude Sickness is actually a milder form of Acute Mountain Sickness (AMS). It is the negative aspect of traveling to high altitudes above 2,400 meters (8,000 ft). With altitude sickness being the mildest form, if untreated. It can escalate to Acute Mountain Sickness very easily, which can require hospitalization and serious treatment.
It does not end there, though. Failing to treat altitude sickness or AMS can actually lead to much more serious symptoms, such as a High-Altitude Pulmonary Edema (HAPE) or a High-Altitude Cerebral Edema (HACE), both of which can be fatal. There is also the chance that a prolonged exposure to high altitudes can cause what is known as Chronic Mountain Sickness. Which then requires the patient to be immediately removed to sea level, and if extreme, can still be fatal even after moving to lower altitudes.
However, there is no hard and fast rule as to who will get altitude sickness, or even that because you did not get it last time you went to Tibet. You will not get it again this time. Nor does being physically fit reduce the risk of AMS.
Causes of Altitude sickness
Altitude sickness is normally caused by an increase in elevation to above 2,400 meters, and the higher you go. The more likely it is that you will suffer from some of the symptoms of altitude sickness. The main reason altitude sickness occurs is due to the oxygen levels in the air at higher altitudes. At sea level, the oxygen in the atmosphere is normally around 21 percent. Which is what our bodies are designed to breathe it. Every time we breathe in, the lungs remove a certain amount of the oxygen from the air. And transferring it to the red blood cells in the body, which carry the much-needed oxygen to all our organs, including the brain.
As you go higher up in altitude, the air gets thinner, due to lower barometric pressure. There is still the same amount of oxygen in the air, the standard 21 percent, but the air is stretched out more. Which means that we take in less air with every breath. This also means that we take in less oxygen with every breath and the lungs do not process enough to meet the needs of the body.
Oxygen level drops at high altitude
The lower oxygen content in the bloodstream means that your limbs start to feel heavy. You feel short of breath, and start to get headaches. These are some of the symptoms of AMS because the body is not getting enough oxygen.
Over time, no more than a couple of days, the body itself automatically adjusts to the increase in altitude and decrease in available oxygen. This is known as acclimatization. As the body acclimatizes, it produces more red blood cells to carry the oxygen around the body. Producing more red blood cells pushes the lungs to extract more oxygen from the air we breathe than at sea level. It can sometimes cause over-oxygenation.
As the body adapts, the increased number of red blood cells carry more oxygen around the body. It brings things back to normal as the organs and brain begin to recover. This acclimatization, however, requires a certain set of requirements of its own in order to be effective as quickly as possible.
Symptoms of altitude sickness
There are many symptoms of altitude sickness, the most common being headaches, nausea, and dizziness. With a shortness of breath and a feeling of being constantly tired. These are not the only symptoms. Any of the given symptoms can mean that you are suffering from altitude sickness, even if you do not have a headache. Any combination of the symptoms, including headaches (although that can also mean you are just dehydrated).It can make that you may have altitude sickness.
The complete list of symptoms of AMS are:
Gastrointestinal Symptoms: Loss of appetite, nausea, or vomiting, excessive flatulence
Nervous Symptoms: Fatigue or weakness, headache with or without dizziness or lightheadedness, insomnia, “pins and needles” sensation
Locomotory Symptoms: Peripheral edema (swelling of hands, feet, and face)
Respiratory Symptoms: Nose bleeding, shortness of breath upon exertion
Cardiovascular Symptoms: Persistent rapid pulse
Other Symptoms: A general feeling of malaise
More severe symptoms may indicate that you are suffering from either Chronic Altitude Sickness or one of the serious and life-threatening forms of AMS. The major symptoms of HAPE (which causes fluid to enter the lungs) are a persistent dry cough, fever, shortness of breath even when resting, and symptoms similar to bronchitis.
The symptoms of HACE, a swelling of the brain, usually include a headache that does not respond to analgesics. An unsteady gait when walking, gradual loss of consciousness, an increase in nausea and vomiting, and any form of retinal hemorrhage.
How to reduce the risk of AMS
While all of this may sound scary, there are some simple ways to reduce the risk of altitude sickness, and part of that is the knowledge of what the symptoms are so that you can do something about it before it gets worse. Not everyone will get altitude sickness, and the symptoms usually subside after one to two days, as long as you follow a few simple rules.
The main recommended way to reduce the risk of AMS is to ascend slowly to high and extreme elevations. Ideally, you should ascend no more than 300 meters per day, before sleeping. Even if you ascend much higher, you should return to a lower altitude no more than 300 meters above your starting point before sleeping. This allows the body to acclimatize slowly over the course of your ascent, reducing the risk of AMS drastically.
However, for many people traveling to Tibet, this is not possible. Since you cannot ask the train to stop every 300 meters in altitude so you can sleep for the night. The other way to reduce the risk of AMS when traveling to Tibet is to Pre-Acclimatize. When traveling to altitudes of 5,000 meters and above. It is recommended to stop at an elevation between 1,500 and 3,000 meters to acclimatize there first. After a day or two at the intermediate altitude, your body should have adapted, and be ready for the next increase in elevation.
The best place for this when traveling to Tibet is at Xining, in Qinghai Province, where the Qinghai Tibet Railway starts. At an elevation of 2,275 meters, it is at an ideal altitude to help you to pre-acclimatize. Once in Lhasa, you should also take a day or two to acclimatize again, thus reducing your chances of getting altitude sickness.
Other means to reduce the risk of AMS are to avoid strenuous activity, such as hiking and climbing, at least for the first 24-48 hours. Alcohol, coffee, and sleeping pills are forms of respiratory depressants. That can reduce the oxygen intake causing the symptoms of AMS even if you are doing nothing. Smoking can also increase the risk of AMS, as the lungs are not able to process enough oxygen, even after producing more red blood cells.
Dehydration is the biggest cause of altitude sickness when traveling to Tibet. Despite the plateau region being a little chilly. It is easier to get dehydrated in high altitudes than in extremely hot weather. Staying hydrated by drinking plenty of water throughout the day can help to reduce the risk of AMS drastically. Alcohol and coffee can also cause dehydration. So you should avoid it.
Available treatments for altitude sickness
There are several treatments for altitude sickness that are widely available over the counter in most Asian countries. Drugs such as acetazolamide – known mostly by its brand name. Diamox – may be of some help to people ascending rapidly to altitudes above 3,000 meters. It can also be taken prior to ascending, under a strict regime of dosage, to help prevent the symptoms from appearing. The recommended dosage, according to the to the Center for Disease Control in the United States. It is 125mg every 12 hours, for at least 24 hours before the ascent to the time when you have reached the highest point of your trip.
However, despite the proliferation of websites that will tell you that you can take Diamox “to prevent getting altitude sickness”. It is not recommended by the CDC to take it as a substitute for a gradual ascent. It can have minor side effects such as tingling in the hands and feet, a massive increase in respiratory speed. A reduction in your ability to maintain consistently increased breathing. Before taking Diamox, or any other brand of acetazolamide. You should first consult your own doctor before leaving home. And listen to his advice based on his knowledge of your health.
If you do get altitude sickness, then ibuprofen, a non-steroidal anti-inflammatory drug available without a prescription. It can help to ease the headaches and nausea associated with AMS. The oxygen enrichment and intervals during acclimatization can help to reduce the symptoms as well. It will prevent the body from acclimatizing at all.