Altitude Sickness: Symptoms, Prevention & When to Seek Help

What is Altitude Sickness?

Altitude sickness is a condition that occurs when the body fails to adapt quickly enough to the reduced oxygen levels at high elevations, typically above 8,000 feet (2,438 metres). As you ascend rapidly, your body doesn't have sufficient time to acclimatise to the thinner air, leading to a range of symptoms that can progress from mild discomfort to life-threatening complications if left untreated. Altitude sickness is a serious concern for anyone venturing to high altitudes, and it's essential to be aware of its signs and take prompt action to prevent severe consequences.

Types of Altitude Sickness

Altitude sickness presents in three main forms, each with varying degrees of severity:

• Acute Mountain Sickness (AMS): The most common and mild form, AMS is characterised by symptoms such as headache, dizziness, nausea, and fatigue.
• High-Altitude Pulmonary Edema (HAPE): This life-threatening condition involves fluid buildup in the lungs, causing severe shortness of breath, cough, and chest tightness.
• High-Altitude Cerebral Edema (HACE): A rare but severe form, HACE is marked by brain swelling, leading to confusion, loss of coordination, and possible coma or death if untreated.

How Common is Altitude Sickness?

Altitude sickness is a frequent occurrence among travellers who ascend quickly to elevations above 8,000 feet. Studies show that up to 25% of people experience symptoms, especially in high-altitude regions like the Himalayas. The risk increases with the rate of ascent and the altitude reached.

What are the Symptoms of Altitude Sickness?

The altitude sickness symptoms can appear within hours of reaching a high elevation and vary depending on the severity of the condition:

Mild (AMS):

• Headache
• Dizziness or lightheadedness
• Nausea and vomiting
• Fatigue and weakness
• Difficulty sleeping
• Loss of appetite

Moderate to Severe (HAPE/HACE):

• Persistent dry cough
• Shortness of breath, even at rest
• Confusion and disorientation
• Unsteady gait or loss of coordination
• Hallucinations or blurred vision
• Racing heart and chest tightness
• Swelling of hands, feet, and face

What Causes Altitude Sickness?

Altitude sickness is caused by a rapid ascent to high elevations, where the reduced air pressure results in lower oxygen availability in the body's tissues, a condition known as hypobaric hypoxia.

What are the Risk Factors for Altitude Sickness?

Several factors can increase your likelihood of developing altitude sickness:

1. Rapid ascent: Ascending too quickly to high altitudes (especially above 8,000 feet) without allowing time for acclimatisation is the primary risk factor.
2. Previous history: If you've experienced altitude sickness before, you're more prone to getting it again.
3. Physical exertion: Engaging in strenuous activities at high altitudes can exacerbate altitude sickness symptoms and increase the risk of complications.
4. Living at low elevations: If you reside at sea level or low elevations, your body may have a harder time adjusting to the reduced oxygen at high altitudes.
5. Certain medical conditions: Pre-existing heart or lung diseases, anaemia, and chronic obstructive pulmonary disease (COPD) can make you more susceptible to altitude sickness.
6. Age: Both young children and older adults may be at higher risk.
7. Alcohol and sedative use: Consuming alcohol or sedatives can worsen symptoms and interfere with acclimatisation.

It's important to note that physical fitness does not necessarily protect against altitude sickness.

What are the Complications of Altitude Sickness?

If left untreated, altitude sickness can progress to life-threatening complications such as HAPE or HACE. These conditions involve fluid accumulation in the lungs or brain, respectively, and can lead to organ failure or death if not addressed promptly.

How is Altitude Sickness Diagnosed?

The diagnosis of altitude sickness is primarily based on a clinical assessment. Doctors will evaluate your symptoms, review your recent altitude exposure history, and perform a physical examination to assess your breathing, heart rate, and mental status. They may also ask about any pre-existing medical conditions that could increase your risk.

What Tests Will Be Done to Diagnose Altitude Sickness?

The diagnostic approach for altitude sickness focuses on excluding other potential causes and assessing the severity of the condition.

Some tests that may be performed include:

1. Physical examination:
   • Measuring your breathing rate and oxygen saturation levels
   • Checking your heart rate and blood pressure
   • Evaluating your coordination and mental status
2. Pulse oximetry: A non-invasive test that measures the oxygen saturation in your blood using a small device placed on your finger.
3. Chest X-ray: If HAPE is suspected, a chest X-ray may be done to look for signs of fluid accumulation in the lungs.
4. Neurological assessment: In cases of suspected HACE, a thorough neurological examination will be performed to check for signs of brain swelling, such as confusion, disorientation, or loss of coordination.
5. Blood tests: While not routinely done, blood tests may be ordered to rule out infections or other underlying conditions if the diagnosis is unclear.

How is Altitude Sickness Treated?

The altitude sickness treatment depends on the severity of the condition:

Mild cases (AMS):

• Rest and avoid further ascent until symptoms improve
• Stay hydrated and consume light, easily digestible meals
• Use over-the-counter pain relievers like acetaminophen or ibuprofen for headache relief
• Consider descending to a lower altitude if symptoms persist or worsen

Oxygen therapy:

• Supplemental oxygen can help alleviate symptoms by increasing the oxygen levels in your blood
• Portable oxygen tanks or concentrators may be used in high-altitude settings

Medications:

• Acetazolamide: This prescription medication can help speed up acclimatisation and reduce symptoms of AMS
• Dexamethasone: A steroid medication used to treat brain swelling in cases of HACE

Severe cases (HAPE/HACE):

• Immediate descent to a lower altitude is crucial and can be life-saving
• Hospital care may be necessary, including oxygen therapy, mechanical ventilation, and intensive monitoring
• Nifedipine: A medication used to treat HAPE by reducing fluid buildup in the lungs
• Dexamethasone: Used to reduce brain swelling in cases of HACE

In remote locations where descent is not immediately possible, portable hyperbaric chambers can be used to simulate lower altitudes and provide temporary relief until evacuation is feasible.

How to Prevent Altitude Sickness?

Preventing altitude sickness is all about allowing your body sufficient time to acclimatise to the reduced oxygen levels at high elevations.

Here are some practical altitude sickness prevention tips to minimise your risk:

1. Ascend gradually: Limit your daily elevation gain to around 1,000 feet (300 metres) above 8,000 feet (2,400 metres). This gives your body time to adapt to the changing conditions.
2. Take rest days: Plan for acclimatisation days every 3-4 days, where you maintain your elevation and engage in light activities to help your body adjust.
3. Stay hydrated: Drink plenty of water and avoid alcohol; limit caffeine as excessive amounts can contribute to dehydration and disturb sleep.
4. Consider preventive medication: If you have a history of altitude sickness or are at high risk, consult your doctor about taking medication before your trip to help speed up acclimatisation.
5. Listen to your body: Be attentive to early signs of altitude sickness, such as headache, nausea, or fatigue. If symptoms develop, stop ascending and rest until they subside. Descend to a lower altitude if symptoms worsen or persist.

What Can I Expect If I Have Altitude Sickness?

If you develop altitude sickness, the course of your recovery will depend on the severity of your symptoms and how quickly you take action. Mild cases of acute mountain sickness (AMS) often resolve within 24-48 hours with rest and acclimatisation. However, if you continue ascending despite symptoms, your condition may worsen and progress to more serious forms like HAPE or HACE, which require immediate medical attention and descent to lower altitudes.

How Long Altitude Sickness Lasts

The duration of altitude sickness varies depending on the individual and the severity of the condition. Mild symptoms of AMS typically improve within 1-2 days if further ascent is halted and supportive care is provided. However, more severe cases involving HAPE or HACE may require longer recovery periods and can take several days to fully resolve, even with proper altitude sickness treatment and descent to lower elevations.

What is the Outlook for Altitude Sickness?

The outlook for altitude sickness is generally good when the condition is recognised early and managed appropriately. Most people recover fully with prompt treatment, which may include rest, acclimatisation, oxygen therapy, and medications. However, if severe forms like HAPE or HACE are left untreated, they can lead to permanent disability or even death. This highlights the importance of altitude sickness prevention, early detection, and swift intervention in ensuring a positive outcome. By being aware of the signs and symptoms, taking steps to acclimatise properly, and seeking medical help when needed, you can greatly improve your chances of a full recovery from altitude sickness.

When to Seek Medical Help?

It's essential to seek immediate medical attention if you experience any of the following symptoms of altitude sickness:

• Severe headache that does not respond to over-the-counter pain medication
• Shortness of breath at rest or a persistent, worsening cough
• Confusion, disorientation, or loss of coordination
• Chest pain, tightness, or palpitations
• Visual disturbances, such as blurred vision, double vision, or seeing halos around lights

Final Thoughts on Staying Safe at High Altitudes

Venturing into high-altitude environments can be an exhilarating and rewarding experience, but it's crucial to approach these adventures with caution and preparation. By understanding the altitude sickness causes, recognising its symptoms, and taking steps to prevent and treat the condition, you can ensure a safer and more enjoyable journey. Remember to ascend gradually, listen to your body, and never hesitate to seek help if you feel unwell.

As a leading chain of diagnostic labs across India, Metropolis Healthcare is committed to providing accurate pathology testing and health check-up services to help you prioritise your well-being. Our team of qualified blood collection technicians offers convenient at-home sample collection, and your test reports are securely shared online via email and our user-friendly Metropolis TruHealth app.

FAQs

What can't I eat or drink with altitude sickness?

It's best to avoid alcohol and caffeine when dealing with altitude sickness, as they can contribute to dehydration and worsen symptoms. Stick to light, easily digestible meals and plenty of water to help your body cope with the altitude change.

How serious is altitude sickness?

Altitude sickness can range from mild discomfort to life-threatening complications. While acute mountain sickness (AMS) is often self-limiting, severe forms like High-altitude pulmonary edema (HAPE) and high-altitude cerebral edema (HACE) can be fatal if left untreated, making early recognition and prompt action crucial.

Can altitude sickness make you throw up?

Yes, nausea and vomiting are common symptoms of altitude sickness, particularly in acute mountain sickness (AMS). These symptoms can also occur in more severe forms of the condition, such as HAPE and HACE.

Do altitude sickness pills work?

Altitude sickness medications like acetazolamide and dexamethasone can be effective in preventing and treating symptoms when used appropriately under medical supervision. However, they should not be seen as a substitute for proper acclimatisation and gradual ascent.

How long does it take to get over altitude sickness?

The recovery time for altitude sickness varies depending on the severity of the condition. Mild cases of acute mountain sickness (AMS) often resolve within 1-2 days with rest and acclimatisation. However, severe cases involving HAPE or HACE may require longer recovery periods and medical treatment.