What Is Altitude Sickness

If you’ve ever walked up a mountain and felt yourself getting sick or dizzy, you may have experienced altitude sickness, also called mountain sickness. This situation happens when you travel to a high altitude (height) too promptly.
It doesn’t happen only to hikers. Just visiting a high-altitude location can create difficulties for some. Symptoms occur when your body adjusts to the lower air pressure and lower oxygen levels at high altitudes.

Who is at risk for altitude sickness?

Anyone can suffer from altitude sickness problems. Your age, gender, and general health don’t seem to hit your risk. You may be at greater risk if you:

Have a lung or heart disease: Your doctor may recommend you to avoid

Women who are pregnant: Talk to your provider before traveling to a high-altitude location.

Living at a low height: Since your body won’t habit to live in higher elevations, you have a more elevated chance for symptoms. If you’re planning a tour to a high-altitude place, be aware of the symptoms of altitude sickness and how to treat it.

History of altitude sickness: Talk to your doctor about prevention and treatment before your next trip.

What are the different forms of altitude sickness?

Most people who get altitude sickness get Acute Mountain Sickness. Higher than 10,000 feet, 75 percent of people will get moderate signs. There are three divisions of AMS:

Mild Acute Mountain Sickness

Signs like light headaches and fatigue don’t interfere with your everyday movement. Symptoms improve after several days as your body adapts. You can likely stay at your current altitude as your body adjusts.

Moderate Acute Mountain Sickness

Symptoms start to oppose your activities. You may experience sharp headaches, nausea, and trouble with coordination. You’ll need to descend to begin to feel more normal.

Severe Acute Mountain Sickness

You may feel shortness of breath, even when you are resting. It can be challenging to walk. You need to settle quickly to a lower elevation and look for medical attention.

Two critical forms of altitude sickness occur less often but are more serious. Both of them can be life-threatening. You need to descend instantly and get medical attention.

HAPE

High-altitude pulmonary edema produces excess fluid in the lungs, causing breathlessness, even when resting. You feel exhausted and sick and may feel like you’re choking.  

HACE

High-altitude cerebral edema involves excess fluid on the brain, causing brain inflammation. You may encounter confusion, lack of coordination, and possibly destructive behavior.

What causes altitude sickness?

Altitude sickness occurs from a quick change in air pressure and air oxygen levels at higher altitudes. If you travel to a high peak, you may have symptoms without giving your body time to settle to lighter oxygen. Even if you’re physically fit and healthy, you can still feel altitude illness.
Additionally, high elevation and lower air pressure can lead to liquid leaking from blood vessels. Researchers don’t know exactly why this happens. This leakage affects fluid to build up in your lungs and brain. Neglecting moderate or critical symptoms can lead to a life-threatening condition.

Symptoms of altitude sickness

You’ll likely feel nauseous and lightheaded. You may vomit and have a headache. Different levels of altitude sickness have different symptoms:

Symptoms of mild, short-term altitude sickness 

Usually, begin 12 to 24 hours after arriving at a high altitude. They lessen in a day or two as your body adjusts. These symptoms include:

• Dizziness.
• Fatigue and loss of energy.
• Shortness of breath.
• Loss of appetite.
• Sleep problems.

Symptoms of moderate altitude sickness 

More intense and worsen instead of improving over time:

• Worsening fatigue, weakness and shortness of breath.
• Coordination problems and difficulty walking.
• Severe headache, nausea and vomiting.
• Chest tightness or congestion.
• Difficulty doing regular activities, though you may still be able to walk independently.

Severe altitude sickness is an emergency

The symptoms are similar to moderate AMS but more severe and intense. If you start experiencing these symptoms, you must be taken to a lower altitude immediately for medical care:

• Shortness of breath, even when resting.
• Inability to walk.
• Confusion.
• Fluid buildup in the lungs or brain.

HAPE

When fluid builds up in the lungs, prevents oxygen from moving around your body. You need medical treatment for HAPE. Symptoms include:

• Cyanosis, when your skin, nails or whites of your eyes start to turn blue.
• Confusion and irrational behavior.
• Shortness of breath even when resting.
• Tightness in the chest.
• Extreme fatigue and weakness.
• Feeling like you’re suffocating at night.
• Persistent cough, bringing up white, watery fluid.

HACE

When the brain tissue starts to swell from the leaking fluid. You need medical treatment for HACE. Symptoms include:

• Headache
• Loss of coordination.
• Weakness.
• Disorientation, memory loss, hallucinations.
• Psychotic behavior.
• Coma.

How is altitude sickness diagnosed?

If you get a headache and at least one other symptom with 24 to 48 hours of moving to a higher elevation, it’s most likely altitude sickness. If you’re climbing, a more experienced climber may recognize symptoms of altitude sickness and guide you to get help.

If you have severe altitude sickness, a healthcare provider will ask about your symptoms, activities, and location. The provider may perform a physical exam, including listening to your chest.

How is altitude sickness treated?

The main treatment for altitude sickness is to move to a lower elevation as quickly and safely as possible. At the very least, do not go higher. If symptoms are mild, staying at your current elevation for a few days might be enough to improve the symptoms.

Other treatments depend on how severe the symptoms are:

• Mild altitude sickness: Over-the-counter medicines can relieve headaches. Other symptoms will improve once your body adjusts or you move to a lower altitude.
• Moderate altitude sickness: Symptoms should improve within 24 hours once you are 1,000 to 2,000 feet lower than you were. Within three days, you should feel completely better.
• Severe altitude sickness, HACE and HAPE: If you have severe symptoms, you must be taken immediately to an elevation that’s no higher than 4,000 feet. Get to a healthcare provider as soon as possible. You may need hospitalization.

What treatments are available for severe altitude sickness?

Treatments depend on your symptoms:

• For fluid in the brain (HACE), you may need dexamethasone, a steroid that helps reduce swelling in the brain. Dexamethasone is sometimes prescribed as a preventive medication.
• For fluid in the lungs (HAPE), you may need oxygen, medication, a lung inhaler or, in severe cases, a respirator.
• If you need more oxygen, a provider might prescribe acetazolamide, which increases your breathing rate, so you take in more oxygen. The medicine helps your body adjust faster to the higher elevation and reduces symptoms of altitude sickness.