Colorado’s mountains offer unparalleled beauty, but rapid elevation gain can lead to Acute Mountain Sickness (AMS), caused by reduced oxygen availability at high altitude. AMS commonly affects visitors traveling quickly to elevations above 8,000 feet, including many popular ski and hiking destinations. While Denver is 5,280 feet, many resort towns are significantly higher, often exceeding 9,000 feet. Understanding the body’s response is the first step in ensuring a safe and enjoyable trip.
Gradual Acclimatization Strategies
The most effective method for preventing altitude sickness involves a slow approach to gaining elevation, allowing the body time to adjust. Acclimatization focuses on managing the rate of ascent, particularly the elevation at which you sleep. Spending a night or two at a moderate altitude, such as Denver, before traveling to higher destinations like Breckenridge or Vail, is a recommended “staging” strategy.
When ascending above 8,000 feet, limit the increase in your sleeping elevation to no more than 1,000 feet per day. For every 3,000 feet of ascent, take a rest day at that elevation before continuing upward.
Avoid strenuous physical activity immediately upon arrival at high altitude. The body is already working harder to compensate for lower oxygen levels. Intense exertion places a heavy strain on the cardiovascular system and increases the risk of developing AMS. Keep activities light, such as a short walk, for the first 24 to 48 hours.
Internal Preparation: Hydration and Substance Avoidance
Maintaining proper internal balance is important for successful acclimatization, especially regarding hydration. High elevation air is typically drier, and the body loses water quickly through increased respiration and altitude diuresis. This fluid loss can rapidly lead to dehydration, which often mimics or worsens AMS symptoms.
Plan to drink an extra 1 to 1.5 liters of water daily, aiming for a total intake of three to four liters of fluid per day. Temporarily avoid substances that act as diuretics or respiratory depressants. Alcohol is a diuretic that speeds up fluid loss and depresses the respiratory drive, hindering the body’s natural adjustment process.
Limit excessive caffeine during the initial days, as it is a mild diuretic and can contribute to dehydration and sleep disruption. Focus instead on a diet high in complex carbohydrates, which require less oxygen for metabolism compared to fats or proteins. Delaying alcohol consumption until you have successfully acclimatized is an effective preventive measure.
Pharmacological Prevention Options
For individuals with a history of altitude illness or those planning a rapid ascent, medical prophylaxis is an option. The primary preventive medication is Acetazolamide (Diamox), a carbonic anhydrase inhibitor that speeds up natural acclimatization.
The drug causes the kidneys to excrete bicarbonate, increasing blood acidity and stimulating the respiratory center. This enhanced breathing rate leads to greater oxygen intake and helps correct respiratory alkalosis. A typical prophylactic dose is 125 milligrams taken twice daily, starting one to three days before ascending and continuing for the first two days at the highest elevation.
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), such as ibuprofen, can manage mild altitude-related headaches. However, NSAIDs only treat the symptom and do not address acclimatization. Consult a physician before your trip to discuss whether Acetazolamide is appropriate for your travel plans and medical history.
Recognizing Symptoms and Immediate Safety Measures
Despite careful preparation, some visitors may experience AMS symptoms, which typically include a headache combined with nausea, fatigue, dizziness, or difficulty sleeping. These mild symptoms usually begin 6 to 12 hours after arrival and should halt any further ascent. Mild AMS often resolves within 24 to 48 hours with rest and hydration.
If symptoms worsen or fail to improve, the definitive treatment is immediate descent to a lower elevation. This is the “Golden Rule” of altitude sickness management, as descending even a few thousand feet brings rapid relief. Be aware of the severe, life-threatening forms of altitude illness: High Altitude Cerebral Edema (HACE) and High Altitude Pulmonary Edema (HAPE).
Signs of HACE include confusion, changes in mental status, or loss of coordination, such as inability to walk a straight line. HAPE is indicated by increasing shortness of breath while resting, a persistent cough, and chest tightness. Severe symptoms require immediate emergency medical attention and rapid descent, as these conditions progress quickly.