Acute mountain sickness

Alternative Names

Treatment

The main form of treatment for all forms of mountain sickness is to climb down (descend) to a lower altitude as rapidly and safely as possible. Supplemental oxygen should also be given, if available.

People with severe mountain sickness may be admitted to a hospital.

Acetazolamide (Diamox) is a drug used to stimulate breathing and reduce mild symptoms of mountain sickness. This drug can cause increased urination. Make sure you drink plenty of fluids. Do not drink alcohol while taking this drug.

Pulmonary edema, the build-up of fluids in the lungs, is treated with oxygen, the high blood pressure medicine nifedipine or phosphodiesterase inhibitors (sildenafil), and, in severe cases, a breathing machine (respirator).

The steroid drug dexamethasone (Decadron) may help reduce swelling in the brain (cerebral edema).

Portable hyperbaric chambers have been developed to allow hikers to simulate their conditions at lower altitudes without moving from their location on the mountain. These new devices are very important if bad weather or other factors make climbing down the mountain impossible.

Outlook (Prognosis)

Most cases are mild, and symptoms improve promptly with a return to lower altitude. Severe cases may result in death due to respiratory distress or brain swelling (cerebral edema).

In remote locations, emergency evacuation may not be possible, or treatment may be delayed. These conditions could adversely affect the outcome.

Possible Complications

• Coma
• High altitude cerebral edema (brain swelling)
• Pulmonary edema

When to Contact a Medical Professional

Call your health care provider if symptoms of acute mountain sickness develop, even if symptoms resolved when returning to a lower altitude.

Call 911 or your local emergency number, or seek emergency medical assistance if severe difficulty breathing develops, or if you notice a lower level of consciousness, coughing up of blood, or other severe symptoms. If unable to contact emergency help, descend immediately, as rapidly as is safely possible.

References

Wright A, Brearey S, Imray C. High hopes at high altitudes: pharmacotherapy for acute mountain sickness and high-altitude cerebral and pulmonary oedema. Expert Opin Pharmacother. 2008; 9(1): 119-27.

Marx J. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 5th ed. St. Louis, Mo: Mosby; 2002:2040-2042.

Murray J, Nadel J. Textbook of Respiratory Medicine. 3rd ed. Philadelphia, Pa: WB Saunders; 2000:1853.

Auerbach PS. Wilderness Medicine. 4th ed. St. Louis, Mo: Mosby; 2001:12-19.