Altitude Sickness: What You Need To Know

Hiking and mountain climbing are hobbies amongst thousands of people. For many, this is more than just a hobby, in fact. There is a significant number of people who go on such adventures for professional purposes. Regardless, individuals who are new to mounting climbing and related activities are at risk of experiencing a condition known as altitude sickness when they are not careful and implement proper precautionary measures. In this post, we’ll take a look at what altitude sickness is, why it happens, who may be at risk and we will discuss the main types of altitude sickness that a person can develop. Furthermore, we will also list symptoms to look out for, provide information that may signal a worse case of the condition, and consider how the condition can be treated to alleviate symptoms and avoid possibly life-threatening complications.

What Is Altitude Sickness?

Altitude sickness is commonly referred to as acute mountain sickness, or AMS, as well. This is a condition that develops when a person exposed their body to an increase in altitude levels at a rate that is faster than it can handle. One particular aspect that makes this condition especially concerning is that some people may develop altitude sickness suddenly even after they have exposed their bodies to high altitude levels previously without experiencing any side-effects before.

What Are The Different Types Of Altitude Sickness?

It is important to understand that there are different types of altitude sickness. While some symptoms and complications associated with the condition is shared among these types of the condition, certain types have specific complications that can make it more harmful and dangerous than the other types. Let’s take a look at the three primary types of this condition that a person may develop when they are exposed to elevated levels of altitude at a fast rate.

  • Acute Mountain Sickness – This is by far the most common type of altitude sickness that people develop and is also seen as the less serious one of the three. The symptoms that a person experiences with acute mountain sickness, or AMS for short, are most often mild and does not cause them alarming complications.
  • High Altitude Pulmonary Edema – A much more serious type of altitude sickness is high altitude pulmonary edema, often called HAPE for short. This condition involves the accumulation of fluids in an affected person’s lungs. When prompt treatment is not administered to a patient, then this condition can certainly lead to their death.
  • High Altitude Cerebral Edema – Another form of altitude sickness that is considered serious and can cause death. High altitude cerebral edema, also called HACE, is considered to be the most serious type of this condition and is also the form that is more likely to cause death. This condition refers to the accumulation of fluids in an affected person’s brain. If medical intervention is not provided promptly, then the patient has a large chance of experiencing life-threatening complications and dying from the condition.

Altitude sickness symptoms

Numerous symptoms may develop in the presence of altitude sickness. Fortunately, it has been established that there are some signs that people can look out for that may signal the development of the condition – when action is taken in a timely manner, they are less likely to experience more severe symptoms or complications. The

first symptoms that develop will usually be experienced within the first day of being exposed to the higher altitude levels. These symptoms may include:

  • Dizziness
  • Nausea and vomiting
  • Breathing difficulties
  • A loss of appetite
  • Sleeping difficulties
  • Fatigue
  • A reduction in energy levels
  • A headache

While most people tend to recover from the symptoms in just a day (sometimes two days), given they provide their body some time to adjust to the new altitude, there are some that continue to experience these symptoms or suffer from more severe symptoms. Acute altitude sickness may cause the affected person to continue experiencing some of the following symptoms:

  • They may develop a headache if they haven’t before. A headache will usually be severe. Medication will not help to reduce the pain.
  • The person may find it becomes difficult to walk and they may have problems with their coordination abilities.
  • The affected person may feel that their chest becomes tighter.

The more serious types of altitude sickness, which would include both HACE and HAPE, can cause the following symptoms to develop:

  • The person may not be able to walk at all
  • The affected individual may come across as being confused
  • Breathing difficulties and shortness of breath – this occurs even when the person has not participated in physical activities
  • The individual affected by altitude sickness may also start to cough. While coughing, they may cough up a frothy substance that is either pink or white.

In more serious cases, a person may also fall into a coma and become completely unresponsive.

What Causes Altitude Sickness?

The body heavily relies on a healthy supply of oxygen all the time to function normally. Every cell in the body depends on oxygen. When the body becomes deprived of oxygen, cells can die, and a person may face life-threatening complications. This is the primary concern among individuals who develop altitude sickness. Higher altitudes mean lower barometric pressure ratings – this, in turn, means the level of oxygen that is available for the human body to absorb from the air becomes reduced. This is why it is important to increase altitude sickness gradually and to take breaks in order to allow the body to adapt to new levels of barometric pressure and oxygen levels.

Altitude sickness medication

The identification of symptoms associated with any type of altitude sickness is important – especially the earlier signs that we covered. When these signs are identified, appropriate measures should be implemented to help reduce the risk of developing a more serious type of altitude sickness and to avoid the various complications that may develop. Individuals who are not expressing symptoms associated with serious types of altitude sickness are advised to avoid any further elevation of altitude. This is usually considered one of the best approaches. The patient may not recover immediately, but they will start to feel better in a day or two. Acetazolamide is often used as a preventative measure but is sometimes also provided when the patient has started to show signs of early-stage altitude sickness. Two other options that are also available that present similar efficiency as Acetazolamide includes Ginkgo Biloba natural plant extracts, as well as the pharmaceutical drug Dexamethasone. Individuals who have already developed acute mountain sickness may benefit from the use of Dexamethasone. Apart from providing the patient with pharmaceuticals to help alleviate symptoms, it is also advised that the patient is descended gradually to help reduce the level of altitude they are exposed to. This can greatly reduce the severity of the symptoms that the patient is experiencing.

Can Altitude Sickness Be Prevented?

The most effective way that a person can reduce their risk of developing altitude sickness is to take things slowly. If the person is new to mountain climbing and has not recently exposed their bodies to the altitudes that they will be exposed to, then they are automatically at a higher risk of developing this condition. It is vital to understand that the human body gets used to the altitude it is exposed to on a daily basis. People who reside in areas with higher altitudes have adapted to the altitude. Individuals who come from an area where the altitude levels are not elevated will need to ensure they gradually increase the altitude exposure. Upon arrival at the destination, it is highly advised that a person spends up to three days to help their body get accustomed to the new altitude level that they are exposing their body to. After this, it is advised to restrict the daily climb to a maximum of 500 meters per day, as this would allow for adequate time to ensure the body can adapt to the increase in altitude levels gradually. Other preventative measures can also help to reduce the risk of developing altitude sickness. This would include avoiding smoking during the “adventure.” Alcohol should also be avoided. Intense exercise routines should be avoided during the first day of being at the location where the person will be climbing upward. A particular type of medication is sometimes also used to help reduce the risk of experiencing symptoms associated with altitude sickness. This medication is known as Acetazolamide and helps the body better adjust to the increase in altitude levels.


Sudden exposures to higher altitudes can put a person at risk of experiencing altitude sickness, a condition that can become life-threatening in some cases. Understanding the symptoms and complications associated with the condition can help a person identify the presence before it becomes a particularly dangerous problem. Furthermore, understanding how the condition can be treated promptly may help to reduce the risk of experiencing further adverse effects and can also save a person’s life.

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