Acute Mountain Sickness (AMS) is a common medical condition that occurs when people travel to high altitudes, usually above 8,000 feet (2,400 meters). The decrease in the partial pressure of oxygen in the air at high altitudes causes AMS, which results in a decrease in the amount of oxygen in the blood.

The severity of AMS symptoms varies, but they usually include headache, nausea, vomiting, fatigue, dizziness, and insomnia. Symptoms typically appear within hours to days of arriving at high altitude, and they may worsen over time. Anyone, regardless of age or physical fitness, can develop AMS, and the risk of developing AMS increases as altitude increases.

The exact cause of AMS is unknown, but it is thought to be a combination of factors such as decreased oxygen supply to the brain, dehydration, and changes in blood flow. When people travel to high elevations, their bodies require time to adjust to lower oxygen levels. Some people are more prone to AMS than others, and no one can predict who will develop the condition.

The best way to avoid Acute Mountain Sickness  (AMS) is to gradually acclimate to high altitude. This usually involves staying at an intermediate altitude for a few days, usually between 5,000 and 8,000 feet (1,500 to 2,400 meters) above sea level, before ascending to higher altitudes. It is critical to stay hydrated during this time and avoid alcohol and sleeping pills, which can cause extensive AMS symptoms.

If  Acute Mountain Symptoms (AMS) symptoms appear, it is critical to rest and avoid further ascent until the symptoms improve. Over-the-counter pain relievers like acetaminophen or ibuprofen can help with headaches and other symptoms. Prescription medications like acetazolamide and dexamethasone may also be used to prevent or treat AMS.

Acute Mountain Sickness(AMS) can progress to more serious conditions such as high altitude pulmonary edema (HAPE) or high altitude cerebral edema (HACE) in severe cases (HACE). These conditions necessitate immediate medical attention and may necessitate a lower altitude descent or evacuation to a medical facility.

What causes acute mountain sickness?

Acute Mountain Sickness(AMS), seems mainly active at an elevation of 2,400M above the sea level. Where the oxygen levels are low and decreased air pressure. While you travel in a chopper, or hike/trek to the mountains, your body may need to properly adapt to the climate in the High Mountains. If you lack proper acclimatization then AMS or altitude sickness occurs.

What are the symptoms of acute mountain sickness?

Acute Mountain Sickness symptoms seem active while moving to a high altitude in the mountains, the following symptoms can be seen :

Mild acute mountain sickness

The beginning of the Acute Mountain Sickness experiences the following symptoms:

  • dizziness
  • headache
  • muscle aches
  • insomnia
  • nausea and vomiting
  • irritability
  • loss of appetite
  • swelling of the hands, feet, and face
  • rapid heartbeat
  • shortness of breath with physical exertion

Severe acute mountain sickness

Severe acute mountain sickness causes more intense symptoms that affect the lungs, heart, and nervous systems

The symptoms of Severe mountain sickness are as below:

  • coughing
  • chest congestion
  • pale complexion and skin discoloration
  • inability to walk or lack of balance
  • social withdrawal

Who is at risk for acute mountain sickness?

Anyone who quickly ascends to a high altitude is at risk of developing acute mountain sickness (AMS). The risk increases as the rate of ascent and altitude are increased. Altitudes above 8,000 feet (2,400 meters) are generally considered high altitudes. However, some people may experience symptoms of AMS at lower altitudes, particularly if they have previously experienced altitude sickness.

The other factors that increase the risk of Acute Mountain Sickness: 

  1. Lack of acclimatization: Failure to allow enough time for the body to adjust to the altitude before ascending further.
  2. Previous AMS, high altitude pulmonary edema (HAPE), or high altitude cerebral edema (HACE) (HACE)
  3. Physical exertion: High-altitude climbing or hiking can increase the risk of AMS.
  4. Age: Older people are more likely to develop AMS.
  5. A cold, cough or other respiratory infection may increase your risk of developing AMS.
  6. Certain medical conditions: People with lung or heart disease, or the sickle cell trait, are more likely to develop AMS.
  7. It’s important to note that the risk of AMS cannot be predicted based on physical fitness or previous altitude experience, as some people are more prone to it than others.

How is acute mountain sickness treated?

A descent to a lower altitude is the best treatment for acute mountain sickness (AMS). If you start experiencing AMS symptoms, the first thing you should do is stop ascending and rest until you feel better. If your symptoms persist or worsen, you should descend as soon as possible to a lower altitude. Aside from descent, there are a number of other treatments that can help alleviate the symptoms of AMS, including:

Oxygen: Supplemental oxygen can help alleviate AMS symptoms and hasten recovery. This may entail using portable oxygen canisters or descending to a lower altitude where the air contains more oxygen.

Medications: A variety of medications can help alleviate the symptoms of AMS. Acetaminophen or ibuprofen for headaches, and medications like acetazolamide or dexamethasone to reduce AMS symptoms and accelerate acclimatization.

Hydration: Staying hydrated can help reduce AMS symptoms. At high altitudes, drinking plenty of fluids, and water can help to prevent dehydration.

Rest: Getting plenty of rest can help reduce AMS symptoms and give your body time to adjust to the altitude.

Gamow bag: A portable hyperbaric chamber capable of simulating a lower altitude and providing temporary relief.

How is acute mountain sickness diagnosed?

Acute mountain sickness (AMS) is typically diagnosed based on a person’s symptoms and history of exposure to high altitudes. There really is no specific test for AMS. A medical professional, on the other hand, may conduct an examination and ask questions about your symptoms and recent altitude exposure to help make a diagnosis.

Headache, nausea, dizziness, fatigue, and difficulty sleeping are some of the most common symptoms of AMS. The severity of the symptoms can range from mild to severe, and they can appear as soon as you reach high altitude.

A medical professional may use a pulse oximeter to measure the oxygen saturation in your blood in some cases. This can assist in determining whether you are getting enough oxygen at high altitude. It should be noted, however, that a normal oxygen saturation reading does not rule out the possibility of AMS.

A neurological exam may be performed in more severe cases to determine the presence of high altitude cerebral edema (HACE), including such changes in mental health status, uncertainty, or trouble walking.

If you have AMS symptoms, it is critical that you seek medical attention, especially if your symptoms are severe or worsening despite treatment. If untreated, AMS can lead to more serious forms of altitude sickness, such as HACE or high altitude pulmonary edema (HAPE), which can be fatal.

How can I prevent acute mountain sickness?

There are several ways to prevent Acute Mountain Sickness while trekking in the mountains:

Gradual ascent: The most effective way to avoid AMS is to gradually ascend, giving your body time to adjust to the altitude. Once you are above 2500 meters (8200 feet), experts recommend that you do not ascend more than 300-500 meters (1000-1500 feet) per day. Taking an additional rest day for every 1000 meters (3281 feet) of elevation gain can also aid in acclimatization.

Hydration: Staying hydrated can aid in the prevention of AMS. Consume plenty of fluids, particularly water, to avoid dehydration at high altitudes.

Diet: A balanced diet rich in carbohydrates, as well as avoiding alcohol and high-altitude diets such as fatty foods, can help reduce the risk of AMS.

Medications: Some medications, such as acetazolamide, can help prevent or help relieve AMS symptoms. However, before taking any medication, you should consult with your doctor.

Supplemental oxygen: Increasing the amount of oxygen available to your body at high altitudes can help prevent AMS. This could include the use of portable oxygen canisters or an oxygen concentrator.

Physical fitness: Becoming physically fit can help reduce the risk of AMS and help you acclimate faster.

Avoiding smoking: Smoking reduces the oxygen-carrying capacity of blood and can cause increased AMS symptoms.