Spotting Altitude Sickness and Taking Action

Altitude Sickness: Two backpackers on a high altitude trail.

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Altitude sickness can affect anyone at high elevations, from mountain hikers to travelers. Understanding its signs and acting swiftly is crucial for your health.

In this post, we’ll explore altitude sickness, its symptoms, causes, and how to respond effectively. Let’s dive in.

Altitude Sickness Explained

What is Altitude Sickness? Altitude sickness, or acute mountain sickness (AMS), happens when you’re at high altitudes above 8,000 feet (approximately 2,500 meters). It occurs because your body hasn’t had enough time to adapt to the lower oxygen levels at higher elevations.

AMS can lead to a range of symptoms, some mild and others severe, which we’ll explore shortly.

How common is it? AMS affects about 40-50 percent of hikers who sleep above 10,000 feet (around 3,000 meters), and approximately 25 percent of those sleeping above 8,000 feet (approximately 2,400 meters)1.

Recognizing the Symptoms

Spotting AMS early is key to ensuring your safety in high-altitude environments. AMS symptoms can range from mild discomfort to severe distress. Here’s what to look out for:

Common Symptoms of Altitude Sickness:

  1. Throbbing headaches: A persistent, pounding headache is a common indicator of altitude sickness. It can be one of the earliest signs.
  2. Lack of appetite: If you suddenly lose interest in food, it could be a sign that your body is struggling with the altitude.
  3. Nausea: Feeling queasy or even vomiting can occur as your body reacts to the change in altitude.
  4. Fatigue: Unexplained tiredness or fatigue, even after a good night’s sleep, can be an early symptom.
  5. Difficulty sleeping: Many people experience trouble sleeping at high altitudes, which can exacerbate other symptoms.
  6. Dizzy spells: Feeling lightheaded or experiencing vertigo is a possible sign.

Severe Symptoms:

In severe cases of altitude sickness, symptoms can become alarming. These include:

  • Confusion: If you or someone you’re with becomes disoriented or confused, it’s a sign of a more serious form of altitude sickness.
  • Fainting: Feeling like you might pass out requires immediate attention.
  • Shortness of breath: Difficulty breathing, especially at rest, is a serious symptom and should not be ignored.
  • Gray or bluish lips or fingernails: If someone’s lips or fingernails start turning gray or bluish, it’s a sign of severe oxygen deprivation.

For severe symptoms, seek immediate medical help and descend to lower ground promptly.

Variations of Altitude Sickness

Altitude sickness can take on different forms, each with unique symptoms and levels of severity. Here’s a quick breakdown of the three main types:

1. Acute Mountain Sickness (AMS):

  • Mild and Common: AMS is the mildest and most common form.
  • Symptoms: Headache, nausea, fatigue, and difficulty sleeping.
  • Treatment: Descend and rest.

2. High-Altitude Cerebral Edema (HACE):

  • Severe Brain Swelling: HACE involves brain swelling.
  • Symptoms: Confusion, balance issues.
  • Treatment: Immediate descent and medical help.

3. High-Altitude Pulmonary Edema (HAPE):

  • Lung Fluid Buildup: HAPE includes lung fluid accumulation.
  • Symptoms: Shortness of breath, cough.
  • Treatment: Swift descent and medical attention.

Distinguishing altitude sickness types is vital for taking the right action. HAPE is life-threatening, so seek medical help urgently.

Immediate Action for Altitude Sickness

Altitude Sickness: A group of backpackers on a high altitude trail during a sunny day

Swift, appropriate action is crucial when altitude sickness strikes. Here’s what to do:

  1. Don’t “Tough It Out”: The most important rule: Don’t push through; take altitude sickness symptoms seriously.
  2. Descend to a Lower Altitude: Descend to lower altitude – the best treatment for all altitude sickness. A slight drop helps symptoms significantly. Act promptly when you notice symptoms; don’t delay.
  3. Rest and Monitor: Descend, rest, and wait for recovery. It may take hours or a day for symptoms to improve. Monitor and seek more help if needed.
  4. Stay Hydrated: Ensure that the affected person stays hydrated. Dehydration can exacerbate altitude sickness symptoms, so encourage drinking fluids.
  5. Avoid Alcohol and Smoking: Altitude sickness can cause breathlessness, so avoid smoking and alcohol, which worsen symptoms by dehydrating you.
  6. Seek Medical Help if Necessary: If severe symptoms persist despite rest and descent, seek medical help promptly. Especially for HACE or HAPE.

Preventing Altitude Sickness

Altitude Sickness: A scenic high altitude mountain trail with backpackers and a guide mule

Prevention is often the best strategy when it comes to altitude sickness. Here are some key steps to minimize your risk and ensure a safer high-altitude experience:

1. Acclimatization:

  • Your body can adapt to higher altitudes if given time. Allow at least two days to reach altitudes between 8,000 to 10,000 feet, and limit daily ascents to no more than 1,000 feet. Remember that your sleeping altitude is crucial; you can ascend higher during the day as long as you sleep at a lower elevation.

2. Stay Hydrated:

  • Drinking plenty of water helps your body adjust to altitude more efficiently and can alleviate symptoms. Dehydration can worsen altitude sickness, so keep yourself well-hydrated.

3. Consult with a Doctor:

If you’re gearing up for an adventure in high-altitude areas, it’s a wise move to consult with a healthcare expert before your journey. They can offer tailored guidance and might even prescribe medicines to help ward off altitude sickness, which is particularly crucial for individuals with heart issues.


Altitude sickness is a real risk for anyone at high elevations, be it hikers or travelers. Quick recognition and the right response are vital for your well-being.

In this post, we’ve covered AMS, its symptoms, causes, and how to react effectively. Whether you’re a seasoned mountaineer or new to high altitudes, knowing the signs and taking action promptly can ensure a safe and enjoyable experience.

Prioritize safety, stay informed, and relish your adventures in the thin air of elevated landscapes. Additionally, think about carrying a personal locator beacon or a satellite messenger to provide an added layer of security and assurance.


Can you get altitude sickness from hiking?

Yes, you can get altitude sickness from hiking. Altitude sickness, also known as acute mountain sickness (AMS), can occur when ascending to high elevations above 8,000 feet. It’s your body’s response to reduced oxygen levels in the thin air at high altitudes. Hikers, particularly those who ascend rapidly without acclimatization, are susceptible to AMS. Recognizing symptoms and taking preventive measures, such as gradual ascent and staying hydrated, can help minimize the risk of altitude sickness during hiking adventures.

Why do I feel weird after elevation hike?

Feeling weird after an elevation hike is not uncommon and can be attributed to altitude-related factors. When you ascend to higher elevations, your body is exposed to thinner air with lower oxygen levels. This can lead to altitude sickness or acute mountain sickness (AMS), which often causes symptoms like dizziness, headache, fatigue, and nausea. AMS can make you feel “weird” or uncomfortable as your body adjusts to the reduced oxygen. It’s essential to recognize these symptoms, descend if necessary, and allow your body time to acclimate when hiking at higher altitudes. Staying hydrated and taking it slow during ascents can also help mitigate these feelings of discomfort.

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