Severe High Altitude Sickness Symptoms & Relief

Have you ever experienced unpleasant symptoms while traveling to the high altitudes of the mountains? If so, you're not alone. In fact, altitude sickness affects 25% to 85% of people traveling to high altitudes.

Although the symptoms of altitude sickness can be quite discomforting, they are typically temporary and not dangerous. However, there are some cases where the symptoms are more severe and require medical treatment.

We will explore the different symptoms of altitude sickness - and the treatments to relieve your symptoms and help you get back to feeling like your old self.

altitude sickness risk factors

What Causes Altitude Sickness?

Altitude sickness occurs due to the sudden decrease in air pressure and the lower concentration of oxygen at high altitudes. 

This can lead to a variety of unpleasant symptoms. The severity of your symptoms usually depends on how quickly you ascended to high heights. 

For example, if you travel slowly to a high-altitude location and spend several days there, your body has time to adjust to the change in pressure. On the other hand, if you quickly ascend – like in a plane – to high altitudes, your symptoms will likely be more severe.

Oxygen at Sea Level
0 feet
Oxygen in Denver, CO
5,280 feet Above Sea Level
Oxygen in the town of Aspen
7,945 feet above Sea Level
Oxygen at the base of Steamboat
8,020 feet above Sea Level
Oxygen at the base of Vail Resort
8,120 feet above Sea Level
Oxygen at the base of Crested Butte
9,380 feet above Sea Level
Oxygen in the town of Breckenridge
9,600 feet above Sea Level
Oxygen at the Summit of Steamboat
10,568 feet Above Sea Level
Oxygen at the Summit of Aspen Mountain
11,212 feet above Sea Level
Oxygen at the Summit of Vail
11,570 feet Above Sea Level
Oxygen at the Summit of Crested Butte
12,162 feet Above Sea Level
Oxygen at the Summit of Breckenridge
12,998 feet above Sea Level

What Are the Different Forms of Altitude Sickness?

There are three different forms of altitude sickness, each with its own set of symptoms and severity. Here's a quick rundown of each:

Acute Mountain Sickness (AMS)

Acute Mountain Sickness (AMS)

Most people who travel to high-altitude areas experience symptoms of acute mountain sickness. There are different categories of AMS, which are determined by their severity. These include:

Mild to Moderate AMS: Symptoms include mild headaches, fatigue, loss of appetite, dizziness, difficulty sleeping, and loss of coordination. 

Severe AMS: The most extreme form of acute mountain sickness, this causes symptoms like shortness of breath, even when at rest. If you have severe AMS, you will need to be taken down to a lower elevation and treated immediately with oxygen.

High-Altitude Pulmonary Edema (HAPE)

High-Altitude Pulmonary Edema (HAPE)

HAPE occurs when excess fluid builds up in the lungs. It's a much rarer form of altitude sickness but has been diagnosed in Colorado. It can be fatal if left untreated. Symptoms include coughing, difficulty breathing, chest tightness, and fatigue. Seek medical help immediately if you suspect you may have HAPE.

High-Altitude Cerebral Edema (HACE)

High-Altitude Cerebral Edema (HACE)

HACE is another highly severe form of altitude sickness in which the brain swells due to excess fluid. Symptoms of HACE include headache, nausea, decreased consciousness, and possible violent behavior. Seek medical attention immediately if you experience any of these symptoms, as they can be life-threatening.

Common Signs and Symptoms of Altitude Sickness

Click each icon to learn more.

Headache Icon


Sleeping Diffculty Icon

Difficulty Sleeping

Shortness Breath Icon

Shortness of Breath

Fatigue Icon

Fatigue / Tiredness

Rapid Pulse Icon

Rapid Pulse

Loss of Appetite Icon

Loss of Appetite

Nausea Icon


Diarrhea Icon


Vomiting Icon


In rare cases, altitude sickness can lead to more severe symptoms such as hallucinations, seizures, or even coma. 

Who is at Risk for Altitude Sickness?

Anyone can get altitude sickness, regardless of age, gender, or fitness level. However, certain groups are at a higher risk than others.

These groups include people who:

  • Are Pregnant:

    Due to the physiological changes that occur during pregnancy, the body may not be able to adapt as quickly or effectively to high altitudes. As a result, pregnant individuals may be more susceptible to altitude sickness and should take extra precautions when traveling to high-altitude locations.

  • Have a Heart or Lung Condition:

    Altitude sickness can also have a more severe impact on individuals with preexisting heart or lung conditions. This is because the decrease in oxygen that occurs at higher altitudes places additional strain on the cardiovascular and respiratory systems. So, if you have a heart or lung condition, consult your provider about whether it is safe to travel.

  • Live in Low Elevation Areas:

    If you live at low elevations (such as near sea level), your body may not be well-adapted to high altitudes. As a result, it is important to take extra precautions when traveling to higher altitudes and reserve your continuous flow oxygen concentrator.

  • Previously Experienced Altitude Sickness:

    If you have had a previous bout of altitude sickness, your body may be more prone to experiencing it again. Be sure to take extra precautions when traveling to high altitudes and reserve your continuous flow oxygen concentrator.

How Can I Prevent Altitude Sickness?

While there is no guaranteed way to prevent altitude sickness, you can do things to help minimize the risk. The key is to allow your body to gradually get used to a higher elevation - otherwise known as "acclimatization." This is not an option for most who are traveling to the high country. Continuous flow oxygen is recommended as it may relieve symptoms that are associated with altitude sickness. 

Tips for proper acclimatization include:

When traveling to higher altitudes, try to spend at least one night at a lower altitude before ascending further. Additionally, if you begin experiencing symptoms of altitude sickness, be sure to contact Alpine Oxygen to rent your portable oxygen concentrator.

In addition to a slower pace, limiting your activity level at higher altitudes is important. This means avoiding strenuous activities such as snow skiing, hiking or mountain climbing if you have yet to be acclimated to the altitude.

Proper hydration is another key part of acclimatization. This is because dehydration can exacerbate the symptoms of altitude sickness, so it is important to keep well-hydrated throughout your trip. Additionally, be sure to minimize your intake of caffeinated and alcoholic beverages, which can have a dehydrating effect on the body.

Millenium M10

What’s the Cure for Altitude Sickness?

Descend… Or: Reserve Oxygen Therapy From Alpine Oxygen Rentals.

The best remedy for the effects of high-altitude sickness is to descend to a lower elevation. However, this is not always possible since you are likely vacationing in a mountainous area and don't want to derail your entire trip.

In this case, supplemental continuous flow oxygen from a rented Oxygen Concentrator is the next best remedy. The concentrated supply of oxygen that the machine provides should help to relieve symptoms quickly. From headaches and nausea to shortness of breath and fatigue, supplemental oxygen can help you get back to enjoying your trip in no time.

Sleeping with Oxygen

When traveling to high altitudes, one of the best remedies for altitude sickness is to sleep with oxygen. Here's a breakdown of your options:

  • The Five Liter Oxygen Concentrator is a great single user unit that comes with nasal   cannulas. It is the quietest concentrator on the market. However, it cannot work with a Non-Rebreather (NRB) Mask or a Y splitter as it may be ineffective with such a low output. Suggested flow rate is 3 LPM.

  • The Ten Liter Oxygen Concentrator is the most powerful concentrator available, If symptoms are mild, a nasal cannula is suitable and more comfortable to sleep with than a NRB mask. Another advantage of a cannula is that two people can use the 10- liter oxygen concentrator simultaneously with the provided Y splitter. The suggested flow rate is 3 LPM for a single user with a cannula 8-10 LPM if using the Y Splitter.

  • If symptoms are more moderate, we recommend using the NRB mask, which will provide the maximum concentration of oxygen. However, it can only be administered to one person when using the mask. Suggested flow rate 10 LPM as there is a reservoir bag that must fill with oxygen before use.

Nasal Cannula
NRB mask

Frequently Asked Questions About Altitude Sickness

Altitude sickness can often be easily identified by a combination of its symptoms and the elevation it occurs. If you experience any of the above-mentioned symptoms while traveling at high altitudes, speak with your healthcare provider as soon as possible or rent your oxygen concentrator.

They can help determine your altitude sickness and prescribe the most appropriate treatment. Depending on the severity and progression of your symptoms, this may involve rest, oxygen therapy, or medications to help alleviate nausea or other associated symptoms.

There is no conclusive evidence that altitude sickness can have long-term effects on the body. In most cases, individuals who experience symptoms of altitude sickness will recover relatively quickly with minimal complications or residual effects.

However, some rare exceptions may occur in which the condition has a more severe and prolonged impact on the body. For example, if you develop HACE or HAPE due to altitude sickness, there may be long-term complications. Although rare, these conditions are caused by fluid buildup in the lungs or brain and can lead to organ damage or death if not treated promptly.

  • Living below 3,300feet
  • Fast rate of ascent to altitude
  • Past History of Altitude Sickness
  • Physical Exertion at Altitude
  • Pre-existing respiratory condition
  • Genetics

Typically symptoms for Altitude Sickness can appear anywhere from immediately upon arrival to 1-3 days after arrival at altitude here in the mountains of Colorado.

Yes and no. “You can’t live without oxygen!” Using supplemental oxygen is not going to force you to want to be on it all the time unless you have a medical condition that requires it.

Yes - an oxygen concentrator can be used on pets with the air of a pet oxygen mask or cage. Just like humans, pets can be sensitive to high elevation, and supplemental oxygen may help alleviate certain symptoms.

Managing Altitude Sickness

As with any health condition, the best way to manage altitude sickness is to be proactive. Pre-order your Alpine Oxygen oxygen concentrator rental.

If you have experienced altitude sickness in the past or need quick relief, Alpine Oxygen has you covered. Our oxygen concentrator rental provides supplemental oxygen for travel through the high altitudes of Colorado and Wyoming. Whether you are experiencing mild or moderate symptoms, our oxygen concentrators will help to quickly alleviate your symptoms so that you can get back to enjoying your trip.

Woman Standing at the top of the mountain