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Altitude Sickness

Altitude Sickness Quick Overview

  • Altitude sickness is due to a rapid ascent to higher altitudes (4800 to 11,200 ft or more) due to the decreasing amount of oxygen (low PO2) that occurs at high altitudes.
  • There are three main types of altitude sickness, acute (mild) altitude or mountain sickness (AMS), high-altitude pulmonary edema (HAPE), and high-altitude cerebral edema.
  • The cause of altitude sickness is the decreasing amount of oxygen available as altitude increases.
  • Early symptoms of altitude sickness include
  • Later symptoms include
    • shortness of breath,
    • extreme fatigue,
    • respiratory failure,
    • cerebral edema,
    • coma, and
    • death.
  • Although many people with mild acute mountain sickness require no medical care, as symptoms worsen, emergency medicine physicians, hyperbaric chamber experts, neurologists, and critical care specialists may need to be consulted.
  • Altitude sickness is usually diagnosed by the patient's clinical condition. Occasionally other tests such as chest x-ray, head CT and/or MRI scans are utilized.
  • Some people can use self-care or home remedies, such as simply descending to a lower altitude, to help reduce symptoms or cure altitude sickness.
  • Medical treatment for altitude sickness may include oxygen, hyperbaric treatment, and medicines such as acetazolamide (Diamox, Diamox Sequels) and/or dexamethasone (AK-Dex, Ocu-Dex) as well as over-the-counter (OTC) pain medications and antinausea medications. However, definitive treatment is for the patient to go to a lower altitude.
  • Most people with self-curing acute mountain sickness do not need a follow-up with a health-care professional. However, those that develop high-altitude pulmonary edema and/or high-altitude cerebral edema may require more extensive follow-up with their doctors.
  • Prevention of altitude sickness is by acclimatizing the body to increasing altitude. Prevention of acute mountain sickness is sometimes with acetazolamide medication.
  • The prognosis for a person that gets altitude sickness depends on the severity of the sickness. Acute mountain sickness can usually resolve with no problems, but patients that develop high-altitude pulmonary edema and/or high-altitude cerebral edema have a more guarded prognosis. About 50% of individuals that develop coma with high-altitude cerebral edema die.
Medically Reviewed by a Doctor on 12/15/2015

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Patient Comments & Reviews

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Acute Altitude Sickness Symptoms

The symptoms of altitude sickness include:

  • A throbbing headache that usually gets worse during the night and when you wake up.
  • Lack of appetite
  • Feeling sick to your stomach. You may vomit.
  • Feeling weak and tired. In severe cases, you do not have the energy to eat, dress yourself, or do anything.
  • Waking up during the night and not sleeping well.
  • Feeling dizzy.

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