Acute Mountain Sickness

Every year, rangers in Rocky Mountain National Park treat countless park visitors with headaches, nausea, dizziness, and a host of other ailments. Many of the people they are treating are suffering from Acute Mountain Sickness (AMS), a generic label applied to symptoms commonly experienced by people visiting high altitudes. The people treated by the rangers aren’t all rock climbers and mountaineers. Many of them are simply enjoying an easy hike or leisurely drive through the park with their family or friends. When travelling above 8,000 feet, everyone is susceptible to AMS.

As a person ascends through the atmosphere, every breath contains fewer and fewer molecules of oxygen. The body’s efforts to compensate for the reduced atmospheric pressure and a lower concentration of oxygen result in the symptoms associated with AMS. In order to avoid worsening symptoms, learn to recognize early signs of AMS.

Symptoms of mild AMS include mild headaches, increased breathing, rapid pulse, nausea, loss of appetite, lack of energy, and general malaise. These are warning signs not to go any higher than you already are.

A person suffering from moderate AMS may begin vomiting, experiencing increased shortness of breath and a headache that doesn’t respond to typical pain relievers. If you or someone you are travelling with experience these symptoms, it is important to descend to lower elevations immediately. Spend at least a day at an elevation where you are comfortable before attempting to ascend again.

If symptoms advance to a lack of balance or coordination, slurring of words, altered mental state, extreme shortness of breathe, a wet or rasping cough, or blue skin, the person may be experiencing severe AMS and their life may be in jeopardy. Go down immediately and seek medical attention.

The easiest way to treat AMS is to prevent it. Remember these simple rules when travelling to altitude. When travelling to high altitude (above 10,000 feet), it is wise to spend at least one night at a moderate elevation before ascending. Climb as high as you like during the day but never spend the night more than 1,000 feet higher than the night before. Remember that if you’re thirsty, you’re already dehydrated. Drink water often. Never take a headache with you when ascending. Treat the headache before going any higher. If you can’t treat it, you’re already too high.

High elevation travelers with preexisting medical conditions are in even greater danger. Conditions such as high blood pressure, diabetes, and conditions affecting the brain, heart, and lungs are among those that may be aggravated by high altitude and can prove deadly in the mountains.

Fortunately, AMS is extremely easy to treat if diagnosed in time. The most effective treatment is simply to GO DOWN.

Last updated: March 31, 2012

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