Altitude Sickness: First Aid Awareness and Management

Altitude sickness occurs when the body does not receive enough oxygen at high elevations. This can lead to symptoms such as headache, difficulty sleeping, fatigue, and loss of appetite. It most often affects individuals who are not accustomed to high altitudes, including travellers, hikers, campers, and skiers.

Mild altitude sickness is very common, and even experienced climbers can be affected. Fitness level, age, or gender does not reliably predict who will develop symptoms. While many cases are mild, altitude sickness can become serious or life-threatening if not recognized early.

Why Altitude Sickness Happens

At higher elevations, the air contains less oxygen. When a person ascends too quickly, the body does not have time to adapt. To compensate, breathing and heart rate increase, which can trigger symptoms.

As the body acclimatizes, symptoms often improve. However, continued ascent without adequate adaptation can cause symptoms to worsen.

Common Signs and Symptoms

Symptoms may begin within 12–24 hours after reaching a higher altitude and can range from mild to severe.

Mild to Moderate Symptoms:

• Throbbing headache, often worse at night or upon waking

• Poor appetite

• Nausea or vomiting

• Fatigue or weakness

• Dizziness

• Difficulty sleeping or frequent waking at night

Severe Symptoms (Medical Emergency):

• Confusion or altered mental status

• Difficulty walking or loss of coordination (ataxia)

• Extreme fatigue or fainting

• Bluish or grey lips or fingernails

⚠️ These severe symptoms may indicate high-altitude cerebral edema (HACE) or high-altitude pulmonary edema (HAPE) and can be fatal without immediate treatment.

First Aid Management for Altitude Sickness

The most effective treatment for altitude sickness is descent to a lower elevation.

For mild symptoms:

• Stop ascending and rest at the current altitude

• Drink plenty of fluids

• Avoid alcohol and strenuous activity

• Use over-the-counter pain relievers such as ibuprofen or naproxen

• Wait until symptoms fully resolve before ascending further

Symptoms may take 12 hours to several days to improve.

For worsening or severe symptoms:

• Descend immediately

• Administer supplemental oxygen if available

• Use a portable pressure chamber if descent is not possible

• Seek emergency medical care

Prescription medications such as acetazolamide may help speed acclimatization. In severe cases, medications like dexamethasone or nifedipine may be used under medical supervision.

Disclaimer

This information is provided for educational and first aid awareness purposes only and does not replace professional medical advice. Severe altitude sickness is a medical emergency. If symptoms worsen or neurological or breathing issues develop, descend immediately and seek emergency care.

Understanding environmental emergencies like altitude sickness is an important component of first aid preparedness. St. Mark James Training, Canada’s largest 100% Canadian-owned and operated first aid and CPR training provider, offers first aid and CPR courses across Canada to help individuals safely respond to outdoor and environmental emergencies.