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Need a guide to altitude sickness and prevention methods? You have come to the right place!

Altitude sickness, also called acute mountain sickness (AMS), occurs when people ascend to high altitudes too quickly. This happens because of reduced oxygen levels and air pressure at higher elevations

You can easily recognize Altitude Sickness at higher altitudes due to their distinctive symptoms. Some of the common symptoms are headache, vomiting, nausea, dizziness, and shortness of breath. Generally, the sickness also affects the bones and joints of the body making your body difficult to walk.

Altitude sickness can be simple and easier to cure but in some conditions, they can prove to be fatal. Some of the fatal cases of Altitude sickness are high-altitude pulmonary edema (HAPE) or high-altitude cerebral edema (HACE).

To prevent altitude sickness, ascend gradually, stay hydrated, avoid alcohol, and consider medications. If symptoms occur, it’s crucial to descend to a lower altitude immediately.

Many travelers to high-altitude areas, such as trekking routes, often experience altitude sickness. So if you want to learn more about sickness, their causes, and preventive measures, this guide is for you.

What is Altitude Sickness?

Altitude sickness is a medical condition that occurs at high altitudes when the body hasn’t had sufficient time to adapt to the decreased oxygen pressure and the environmental conditions typical of high altitude, leading to feelings of unwellness.

Typically, altitude sickness affects high-altitude trekkers and mountain climbers. With increasing altitude, the air becomes thinner, causing a decrease in the amount of oxygen the body receives.

Starting ascent to high altitudes without sufficient acclimatization to the elevation or climate can lead to the body’s failure to adjust to the reduced oxygen levels. As a result, breathing may become difficult, and feeling ill often manifests as the primary symptom of altitude sickness.

Cause of Altitude Sickness 

Here are some of the main culprits for Altitude Sickness.

  • Rushing to climb altitudes: The main reason for altitude sickness is rushing your trek or climbing toward the top of the altitude. When your body doesn’t get time for acclimatization with higher altitude and air pressure, the body starts becoming weak. This is the reason expert guides and veteran trekkers keep at least one day as an acclimatization day.
  • Take Alcohol: The trekkers are advised not to take alcohol whenever they are trekking at high altitudes. Especially if the trekker is a beginner then taking alcohol is strictly prohibited.
  • Dehydration: Dehydration is another major cause of altitude sickness. So whenever you are climbing altitudes you must always keep your body hydrated by constantly drinking water.
  • Living near sea level: If you are living near sea level and quickly climb high altitude, you are more prone to altitude sickness. At sea level, the oxygen level is very high and the air pressure is higher. Your body is affected by the high oxygen level and high air pressure. When you quickly ascend to a higher altitude, the air pressure decreases, and there’s less oxygen per breath. This sudden change will impact the oxygen intake in your body and will make you more likely to fall ill.

Therefore, these factors represent common causes of altitude sickness. It is crucial to monitor individuals closely if you intend to prevent the onset of illness.

What will happen when you’re at high altitudes?

As you start to gain altitude, your body will start taking less oxygen since the amount of oxygen starts to decrease. As the altitude increases over 2500m  the chances of altitude sickness increase.

As your body craves more oxygen your metabolism starts to increase. Normally in this situation, you will feel hungry and thirsty but due to increased metabolism, you will not get hungry. You will start sweating more which also causes dehydration in the long run.

So it is essential to not rush climbing the altitude. The likelihood of altitude sickness increases when you rush towards the high altitude. Also, keep yourself warm all the time, especially during the nighttime.

At higher altitudes, you may not feel as hungry or thirsty, but it’s essential to eat and drink more than usual to prevent dehydration and altitude sickness. Keep hydrated by drinking water consistently to avoid these risks.

 Symptoms of Altitude Sickness

As climbers go higher, the risk of altitude sickness goes up. It’s important to know its symptoms to treat it before it becomes dangerous. The severity of symptoms varies depending on the individual’s level of susceptibility to altitude sickness.

Mild symptoms of Altitude sickness are listed below:

  • Appetite loss
  • Fatigue
  • Vomiting or nausea
  • Rapid heart rate (pulse)
  • Shortness of breath
  • Headache
  • Difficulty in sleeping
  • Dizziness

Altitude sickness can be lot severe. Some severe symptoms of altitude sickness are listed below:

  • Congestion or chest tightness
  • Cyanosis 
  • Inability to walk in a straight line
  • Difficulty breathing
  • Withdrawal
  • Temporary Paralysis
  • Cough
  • Blood on cough
  • Decreased consciousness
  • Confusion
  • Pale or gray complexion

It is very important to figure out whether it’s mild or severe symptoms quickly for adequate treatment.

How to Cure Altitude Sickness?

Altitude sickness often occurs at altitudes above 2500m. When symptoms appear, prompt treatment is essential. While there’s no instant cure, it’s vital to effectively manage altitude sickness to alleviate its effects.

1. Descend, Descend, Descend: Moving to a lower altitude is the most crucial action if you experience altitude sickness, as it allows your body to recover from the reduced oxygen levels. Even a small drop in altitude can significantly improve your condition.

2. Rest and Acclimatize: Once you experience symptoms, it’s important not to push yourself further. Give your body time to adjust to the altitude by resting and avoiding strenuous activities. Acclimatization schedules recommend ascending gradually, with rest days incorporated, especially above 2,500 meters.

3. Stay Hydrated: At high altitudes, drink lots of water, even if you’re not thirsty. Aim for 4-7 liters daily to prevent dehydration, which can make symptoms worse.

4. Consider Medication: Medicines like Diamax or nifedipine can assist in preventing or managing altitude sickness; however, always consult a doctor before taking any medication, as they can guide the suitable dosage tailored to your individual health and risk factors.

5. Seek Medical Attention if Necessary: Seek immediate medical attention if symptoms are severe or do not improve with descent and rest. This is particularly crucial for cases of High Altitude Pulmonary Edema (HAPE) or High Altitude Cerebral Edema (HACE), which necessitate specialized treatment.

What are the Types of Altitude Sickness?

Altitude Sickness can affect you in several ways but there are three main types. Let’s get into it.

Acute Moutain Sickness (AMS)

Over 25% of climbers ascending too quickly above 2500m experience Acute Mountain Sickness (AMS). This occurs because the body finds it challenging to adapt to reduced oxygen levels, resulting in weakness and various symptoms of illness.

Acute Mountain Sickness is not a serious kind of Altitude sickness. You can cure AMS with a simple medicine like Diamax and by just lowering the altitude.

High Altitude Pulmonary Edema (HAPE)

High Altitude Pulmonary Edema is another type of altitude sickness. This illness typically begins at altitudes above 2500m. However, HAPE is way more dangerous and fatal than AMS.

During HAPE, your lungs are affected as the sickness affects the function of the lungs. Interruption of lung function occurs due to capillaries within the lungs leaking and retaining fluid, which leads to breathing difficulties.

If you suffer from HAPE, you will start to feel pain in the chest. The victims will start coughing profusely and they will find it very difficult to breathe. When any trekkers start complaining about chest pain, start coughing, and if their lips start turning blue, they are suffering from HAPE.

HAPE can be triggered by a rapid change in altitude, but factors like dehydration and inadequate nutrition can also contribute to its onset. Trekkers with pre-existing respiratory issues are particularly susceptible to HAPE.

The difference between AMS and HAPE is very serious and fatal, unlike AMS. The patient needs to be treated immediately by providing an emergency supply of oxygen. The patients must be lowered at a fast pace and must be kept in constant diagnosis until they are removed from danger.

High Altitude Cerebral Edema (HACE)

HACE is the most dangerous kind of altitude sickness which affects the brain of the patient. It generally occurs above the altitude of 3600m. It is known as mountain madness. After affecting from HACE, the brains of the victim swell due to lack of oxygen.

As the brain requires a constant supply of oxygen, a lack of oxygen will create stress in the cerebral sector. To compensate, your body tries to increase blood flow to the brain. This can lead to fluid build-up and increased pressure within the skull, causing the brain to swell.

Once the brain is swollen the body starts feeling haziness, confusion, weakness, and delusion. Once the symptoms start showing they must be treated immediately. If the condition is not treated immediately the victim can suffer ataxia, seizures, and coma. It can also be fatal as many patients have died of HACE.

HACE is very dangerous and there is no guarantee of treatment. The quickest way of treating the sickness is by lowering the altitude rapidly. Once the symptoms are recognized you will have to drop at least 1000m. As the body starts getting more oxygen it can start the recovery process.

Once altitude has been lowered, immediate oxygen supplementation is crucial for the affected individuals. Portable oxygen tanks or hyperbaric chambers can be utilized to stabilize their condition and facilitate recovery.

Preventive Measures for Altitude Sickness 

It’s better to prevent altitude sickness than waiting to cure it. Some of the best preventive measures are

  • Climb gradually: Aim for no more than 300 meters (1,000 feet) of elevation gain per day above 2,500 meters (8,000 feet).
  • Rest days are crucial: Schedule them every 3,000 meters (10,000 feet), especially above 4,267 meters (14,000 feet).
  • Sleep low, climb high: If possible, descend to a lower altitude to sleep each night.
  • Hydrate: Drink 2-4 liters of water daily, even if you don’t feel thirsty.
  • Drink Electrolytes: Add electrolyte tablets or sports drinks to replenish lost minerals.
  • Eat light, but often: Choose easily digestible carbs and protein for sustained energy.
  • Avoid alcohol and caffeine: They dehydrate and worsen symptoms.

Tej Bahadur Gurung

With an experience of almost two decades, founder Mr. Tej Bahadur Gurung has established Nepal Alternative Treks as a widely recognized and reliable tourism operator. His degree in Tourism Studies and devotion to the sector has given him in-depth knowledge about trekking, climbing, cultural, and geological aspects of the country. He is a pioneer in introducing the concept of ‘off-beaten tracks’ and ‘alternative routes’ as well as treks and tour packages surrounding it.

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