What is altitude sickness?

Altitude Sickness

Altitude sickness

Altitude sickness occurs when people go to a higher altitude too quickly and do not get enough oxygen in the air they breathe. Common symptoms include having a headache and not feeling like eating.

Altitude sickness most often occurs at altitudes above 8000 ft (2500 m). In mild cases, the symptoms can be treated with over-the-counter medicine. But the best way to treat altitude sickness is to go to a lower altitude quickly.

Altitude sickness can be deadly. People who have symptoms should not go to a higher altitude until the symptoms are gone. Symptoms of confusion, feeling faint, or not being able to walk in a straight line mean the condition is life-threatening.

What are the symptoms of altitude sickness?

The symptoms of altitude sickness may be mild to severe. Symptoms may include:

  • A headache, which may get worse during the night and when you wake up.
  • Weakness.
  • Feeling sick to your stomach. You may vomit.
  • Feeling dizzy.
  • Being confused.
  • Breathing problems.

When altitude sickness is severe, it may be deadly.

Your symptoms may not start until a day after you have been at a high altitude. Many people say altitude sickness feels like having a hangover.

How is altitude sickness treated?

The best treatment for altitude sickness is to go to a lower altitude. But if you have mild symptoms, you may be able to stay at that altitude and let your body get used to it. Symptoms often occur if you have just arrived at a mountain resort from a lower altitude.

If you stay at a high altitude, rest. You can explore the area, but take it easy. Limit any walking or activity. Drink plenty of water, but do not drink alcohol. Do not go to a higher altitude until your symptoms go away. This may take from 12 hours to 3 or 4 days.

For the headache, you can take an over-the-counter medicine, such as ibuprofen (Advil, Motrin) or naproxen (Aleve). Do not give aspirin to anyone younger than 20. Aspirin has been linked to Reye syndrome, a serious illness. You may also use medicine to reduce feeling sick to your stomach or other symptoms.

A doctor can give you acetazolamide (Diamox). This speeds up how fast your body gets used to the higher altitude. Nifedipine (Procardia) and dexamethasone are also used for altitude sickness. You may also be able to use oxygen or a specially designed pressure chamber to treat altitude sickness.

Go to a lower altitude if your symptoms are moderate to severe, they get worse, or medicine or oxygen treatment does not help. Go down at least 1500 ft (450 m) . Go to a lower altitude as fast as you can or get emergency help if someone with you has severe symptoms such as being confused or not being able to walk straight. Go with the person. Never let someone with severe altitude sickness go down alone.

How can you prevent altitude sickness?

You may be able to prevent altitude sickness by taking your time when you go to high altitudes and using medicine in advance.

  • If you go to altitudes higher than 8,000 feet (ft), try to spend at least a night at a medium altitude before going higher. For example, in the United States, spend a night in Denver before going to the Rocky Mountains.
  • Do not fly into high-altitude cities. If this is not possible, avoid large meals, alcohol, and being very active after you arrive. Rest, and drink plenty of liquids. If you have symptoms, do not go higher until they have gone away.
  • Sleep at an altitude that is lower than the altitude you were at during the day. For example, if you ski at 9,500 ft during the day, sleep the night before and the night after at 8,000 ft.
  • You may consider taking medicines such as ibuprofen, acetazolamide (Diamox) or dexamethasone before traveling to high altitudes. These medicines may prevent or lessen symptoms. Talk to your doctor about this.

How is altitude sickness diagnosed?

If you are at a high altitude, your doctor may think you have this condition. Your doctor will ask you questions about your symptoms and examine you. To rule out other conditions, your doctor may ask if you have been drinking fluids or alcohol or using any medicines, or if you have a cold or the flu.

If you are hiking or camping, you and those with you need to know the symptoms of altitude sickness. People often mistake altitude sickness for the flu, a hangover, or dehydration. As a rule, consider your symptoms to be altitude sickness unless you can prove they are not.

How can you care for yourself when you have altitude sickness?

Going to a lower altitude can help you feel better. If you stay at a high altitude, rest, and don't go any higher. Limit any walking or activity. Avoid alcohol. Try an over-the-counter pain medicine if you have a headache. Take these and any medicines prescribed by your doctor as instructed.

What causes altitude sickness?

Air is "thinner" at high altitudes. When you go too high too fast, your body cannot get as much oxygen as it needs. So you need to breathe faster. This causes the headache and other symptoms of altitude sickness. As your body gets used to the altitude, the symptoms go away.

What is altitude sickness?

Altitude sickness occurs when you cannot get enough oxygen from the air at high altitudes.

It happens most often when people who are not used to high altitudes go quickly from lower altitudes to 8,000 ft or higher. When you go too high too fast, your body cannot adjust.

Altitude sickness can range from mild to life-threatening. With good planning, such as ascending slowly or taking certain medicines, it is often preventable.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.

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