Understanding Altitude Sickness: Causes, Symptoms, and Prevention

When traveling to higher elevations, it's important to be aware of altitude sickness, also known as mountain sickness. This condition can affect anyone, regardless of age or fitness level, and can cause a range of symptoms. In this article, we'll explore what causes altitude sickness, the different types, symptoms to watch out for, and how to prevent it.

What Causes Altitude Sickness?

Altitude sickness occurs when you travel to a higher elevation too quickly. As you go up, the air pressure drops, and there is less oxygen available. Your body needs time to adjust to this change in pressure. If you live at a moderately high altitude, your body is already accustomed to the air pressure. However, if you travel to a place at a higher altitude than you're used to, you may experience altitude sickness.

Types of Altitude Sickness

There are three levels of altitude sickness:

1. Acute Mountain Sickness (AMS): This is the mildest form and is very common. Symptoms can feel like a hangover and include dizziness, headache, muscle aches, and nausea.

2. High-Altitude Pulmonary Edema (HAPE): This is a buildup of fluid in the lungs that can be very dangerous and even life-threatening. It is the most common cause of death from altitude sickness.

3. High-Altitude Cerebral Edema (HACE): This is the most severe form of altitude sickness and happens when there's fluid in the brain. It is also life-threatening, and immediate medical attention is necessary.

Symptoms of Altitude Sickness

Common symptoms of altitude sickness include:

• Headache

• Dizziness

• Nausea and vomiting

• Fatigue and loss of energy

• Shortness of breath

• Sleep problems

• Loss of appetite

Symptoms usually appear within 12 to 24 hours of reaching a higher elevation and improve within a day or two as your body adjusts. However, if you have a more moderate case, symptoms may feel more intense and not improve with over-the-counter medications. You may experience worsening shortness of breath, fatigue, loss of coordination, and trouble walking.

In severe cases of HAPE or HACE, additional symptoms may include:

• Confusion

• Shortness of breath even at rest

• Inability to walk

• A cough that produces a white or pink frothy substance

• Coma

Who is at Risk for Altitude Sickness?

Anyone can develop altitude sickness, even Olympic athletes. Factors that may increase your risk include:

• Rapid ascent to higher elevations

• High altitude of the destination

• Sleeping at a high altitude

• Physical activity at a high elevation

• Age (young people are more susceptible)

• Previous history of altitude sickness

Certain medical conditions, such as diabetes or lung disease, do not automatically increase your risk. However, people with sickle cell anemia, COPD, unstable angina, high-risk pregnancy, heart failure, cystic fibrosis, or recent heart attacks or strokes may have difficulty tolerating the change in altitude.

Treatment for Altitude Sickness

If you experience a headache and at least one other symptom of altitude sickness within a day or two of changing elevation, you may have altitude sickness. For mild symptoms, rest at your current altitude to see if your body adjusts. Stay warm, drink plenty of fluids, and avoid going any higher until your symptoms resolve.

If your symptoms are severe or do not improve after a couple of days, descend to a lower elevation as quickly as possible. Avoid exertion and seek medical help. Your doctor may perform a chest examination, X-ray, MRI, or CT scan to check for fluid in your lungs or brain. Treatment for HACE may include the steroid dexamethasone, while HAPE requires supplemental oxygen and possibly medications, in addition to moving to a lower altitude.

Preventing Altitude Sickness

The best way to prevent altitude sickness is through acclimatization, which allows your body to gradually adjust to the changes in air pressure. Some tips for acclimatization include:

• Start your journey below 10,000 feet

• If flying or driving to a higher elevation, stop at a lower destination for at least a full day before going higher

• If walking, hiking, or climbing above 10,000 feet, only ascend an additional 1,000 feet per day

• Talk to your doctor about whether medications like acetazolamide are right for you to prevent altitude sickness

• Rest for at least a day for every 3,000 feet of elevation gain

• Climb high and sleep low: If climbing over 1,000 feet in a day, descend to a lower altitude to sleep

• Drink 3-4 quarts of water daily and ensure about 70% of your calories come from carbohydrates

• Avoid tobacco, alcohol, and medications like sleeping pills for the first 48 hours

• Limit vigorous exercise for the first 48 hours

• Learn to identify the early signs of altitude sickness and descend to a lower elevation if symptoms appear

By understanding the causes, symptoms, and prevention strategies for altitude sickness, you can better prepare for your high-altitude adventures. Remember to listen to your body, take necessary precautions, and seek medical attention if symptoms worsen or persist. With proper planning and acclimatization, you can safely enjoy the beauty of high-elevation destinations.

For more information on altitude sickness, visit:

• CDC - Altitude Sickness

• NHS - Altitude Sickness

• WebMD - Altitude Sickness

The Bottom Line

Prevention through gradual ascent is far more effective than treatment, as descent is often the only cure for severe cases. Recognition of early warning signs—persistent headache unrelieved by rest and pain medication—can prevent life-threatening complications. If you're planning high-altitude travel or experiencing concerning symptoms, Doctronic can provide personalized guidance on prevention strategies and when to seek immediate care.