Acute Mountain Sickness (AMS)

Altitude sickness describes several symptoms that happen to your body when you’re exposed to a higher elevation within a short period of time.

Altitude sickness is common when people are traveling and either climbing or being transported to a higher elevation quickly. The higher you climb, the lower the air pressure and oxygen levels get. Our bodies can handle the shift, but they need time to adjust gradually.

Here are some things you can do to prevent yourself from getting altitude sickness.

Climb slowly

Your body needs about two to three days of the slow-motion at higher altitudes in order to adjust to the changes in weather. Avoid flying or driving directly to high altitudes. Instead, go up (higher) each day, stop to rest, and continue the next day. If you have to fly or drive, pick a lower altitude to stay at for 24 hours before going all the way up.

When traveling on foot, plan your trip up with stopping points at lower elevations before reaching your final destination. Try to travel no more than 1,000 feet each day, and plan a rest day for every 3,000 feet you go higher.

Eat carbs

It’s not often we’re told to eat extra carbohydrates. But when you’re at a higher altitude, you need more calories. So pack plenty of healthy snacks, including lots of whole grains.

Avoid alcohol

Alcohol, cigarettes, and medications like sleeping pills can make altitude sickness symptoms worse. Avoid drinking, smoking, or taking sleeping pills during your trip to higher altitudes. If you want to have a drink, wait at least 48 hours to give your body adjust before adding alcohol into the mix.

Drink water

Staying hydrated is also important in preventing altitude sickness. Drink water regularly during your climb.

Take it easy

Climb at a pace that’s comfortable for you. Don’t try to go too fast or engage in exercise that’s too strenuous.

Sleep at lower Altitude

Altitude sickness usually gets worse at night when you’re sleeping. It’s a good idea to do a higher climb during the day and then return to a lower altitude to sleep, especially if you plan on climbing more than 1,000 feet in one day


Usually, medication isn’t prescribed unless flying or driving, trekking, or climbing to high altitude is unavoidable. There’s some evidence that taking Acetazolamide (the former brand name of Diamox) two days before a trip and during your trip can help prevent altitude sickness.

Acetazolamide is a medication typically used to treat glaucoma. However, it can also help to prevent altitude sickness. You need a prescription from your doctor to get it.

It’s also important to know that you can still get altitude sickness even when taking Acetazolamide. Once you start having symptoms, the medication won’t reduce them. Getting yourself to lower altitude again is the only effective and cheaply guaranteed treatment.

Some Vital Keys to prevent Acute Mountain Sickness

  1. Climb the mountain gradually.
  2. Make light your day backpack
  3. If you have moderate AMS you should stop to climbIf there is no improvement after a few hrs (or overnight), you should have to be descended and after recovery, you can ascent up.
  4. If you have severe AMS (persistent vomiting severe, persistent headache, progressing fatigue, or extreme tiredness, delirium, confusion and coma, loss of coordination, rapid breathing after resting (25 or more per minute) severe cough, coughing pinkish sputum, rapid heart rate after resting (110 or more beats per minute) blueness of face and lips, and low urine output (less than 500ml) the only treatment is descent! descent! descent! (600m to 1000m and oxygen) if you do not have available oxygen, do not wait till the next morning. Strong person or Helicopter, Doctor, and Rescue team give accompany to the victim avoiding exertion as much as possible.Stop for a day or two for the rest every 2,000 feet (600 meters) while climbing above 8,000 feet (2,400 meters).Go high but sleep at a lower altitude when possible.

Learn how to recognize early symptoms of mountain sickness.

Alternative Names................................

High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema.

Symptoms of Altitude Sickness

Mild symptoms include

  1. Not feeling well overall.
  2. Trouble sleeping.
  • Loss of appetite.

If you develop mild altitude sickness, you should stop climbing any higher and return to a lower elevation level. These symptoms go away on their own when you move to a lower altitude, and as long as they’re gone you can start the trip again after a couple of days of rest.

Severe symptoms include

  1. More intense versions of the mild symptoms.
  2. Feeling out of breath, even when you’re resting.
  3. Coughing that won’t stop.
  4. Tightness in the chest.
  5. Congestion in the chest.
  6. Trouble walking.
  7. Seeing double.
  8. Confusion.
  9. Skin color changing to gray, blue, or paler than normal.

This means your altitude symptoms are more advanced. If you notice any of these, get to a lower altitude as soon as possible, and seek medical attention. Severe altitude sickness can cause fluid in the lungs and brain, which can be deadly if left untreated.

Bottom Line

It’s hard to predict exactly how your body will react to high altitudes because everyone is different. Your best defense against altitude sickness is not to climb too high too fast and to be prepared by practicing the tips above.

If you have any existing medical conditions, like heart problems, trouble breathing, or diabetes, you should talk to your doctor before traveling to high altitudes. These conditions may lead to additional complications if you get altitude sickness.

What are HAPE and HACE?

Altitude sickness. ... Acute mountain sickness can progress to high altitude pulmonary edema (HAPE) with associated shortness of breath or high altitude cerebral edema (HACE) with associated confusion. Chronic mountain sickness may occur after long term exposure to high altitude.

HACE: High-altitude pulmonary edema (HAPE) is a progression of HACE, but it can also occur on its own. Excess fluid builds up in the lungs, making it difficult for them to function normally.

Symptoms of HAPE include

  1. Increased breathlessness during exertion.
  2. Severe coughing.
  • Weakness.

HACE, HACE commonly include confusion, loss of consciousness, fever, (hallucination), (delirium) rapid heartbeat, tiredness, and an altered mental state

If HAPE isn’t treated promptly by decreasing altitude or using oxygen, it can lead to death.

What Causes Altitude Sickness?

If your body doesn’t acclimate to high elevations, you may experience altitude sickness. As altitude increases, the air becomes thinner and less oxygen-saturated. Altitude sickness is most common at elevations above 2,438 meters (8,000 feet). Twenty percent of hikers, skiers, and adventurers traveling to high elevations between 2,438 meters (8,00,0), and the number increases to 50 percent at elevations above 5,486 meters, (18,000 ft) experience altitude sickness.

Keys Causes

Acute mountain sickness is caused by reduced air pressure and lowers oxygen levels at high altitudes.

The more rapidly you ascend or go at high altitude, the more you are likely to get acute mountain sickness.

You are at higher risk for acute mountain sickness if

You live at low or near sea level and travel to a high altitude.

You have had the illness before.

Who is at risk for Altitude Sickness?

You’re at low risk if you’ve had no previous episodes of altitude sickness. Your risk is also low if you gradually increase your altitude. Taking more than two days to climb 8,200 to 9,800 feet can help reduce your risk.

You're risk increases if you have a history of altitude sickness. You’re also at high risk if you ascend rapidly and climb more than 1,600 feet per day.

Exams and Tests

The health care provider will examine you and listen to your chest with a stethoscope. This may reveal sounds called crackles (rales) in the lung. Rales may be a sign of fluid in the lungs.

Tests may include

  1. Blood tests
  2. Brain CT scan
  3. Chest x-ray
  4. Electrocardiogram (ECG)


Early diagnosis is important. Acute mountain sickness is easier to treat in the early stages.

The main treatment for all forms of mountain sickness is to climb down (descend about 600 meters to 1000 meters) to a lower altitude as rapidly and safely as possible. You should not continue climbing if you develop symptoms.

Extra oxygen should be given, if available

People with severe mountain sickness may need to be admitted to a hospital. Acetazolamide (Diamox) may be given to help you breathe better. It can help reduce mild symptoms. This medicine can make you urinate more often. Make sure you drink plenty of fluids and avoid alcohol when taking this drug. This medication works best when taken before reaching a high altitude.

If you have fluid in your lungs (pulmonary edema), treatment may include.

Headache; (Paracetamol, Aspirin)

Severe headache; (Code Ine)

Nausea; (Compazine)

Acute Mountain  Sickness; (Diamax 250mg) 2 times

If symptoms are moderate or severe; (Dezamethazone, Oxygen,)

A high blood pressure medicine; (Nifedipine, Adalat 20mg) Every in 6hrs

Beta agonist inhalers; to open the airways

Breathing machine in severe cases

High Altitude Pulmonary Edema; (PAC bag) Portable Hyperbaric Chamber

Cerebral Edema; (Dexamethasone, Decadron) may help to reduce swelling the brain

Medicine to increase blood flow to the lungs; phosphodiesterase inhibitor (such as sildenafil)

Portable hyperbaric chambers (PAC bags) allow hikers to simulate conditions at lower altitudes without actually moving from their location on the mountain. These devices are very helpful if bad weather or other factors make climbing down the mountain impossible.

Outlook (prediction)

Most cases are mild. Symptoms improve quickly when you climb down the mountain to a lower altitude.

Severe cases may result in death due to lung problems or brain swelling, called cerebral edema.

In remote locations, an emergency evacuation may not be possible, or treatment may be delayed. This can have a negative effect on your outcome.

The outlook depends on the rate of descent once symptoms begin. Some individuals are more prone to developing altitude-related sickness and may not respond as well.

Possible Complications

Coma (unresponsiveness)

Fluid in the lungs (pulmonary edema)

Swelling of the brain (cerebral edema), which can lead to seizures, mental changes, or permanent damage to the nervous system


When to Contact a Medical Professional:

Call your provider if you have or had symptoms of acute mountain sickness, even if you felt better when you returned to a lower altitude.

Call Helicopter rescue or your local emergency number if you or another climber has any of the following symptoms:

Severe breathing problems

If you have Severe Case as like HAPE or HACE

Coughing up blood

Climb down the mountain as quickly as possible and safely.