Altitude Sickness on the Manaslu Trek and How to Prevent It?

Altitude sickness is a condition that occurs when your body is unable to adapt to the reduced oxygen levels at high altitudes. The trekkers who gain altitude too quickly without adjusting to the higher Himalayan environment may develop altitude sickness at altitudes over 2,500 m. 

During the Manaslu Circuit Trek, you will be at different high-altitude areas with its highest point at Larkya La Pass (5,106m). So, there is a significant risk of altitude sickness. The trek is moderate to challenging and lengthy, taking almost 13 to 15 days to complete. It involves several uphill ascents. So, there is also a likelihood of trekkers facing altitude problems if they aren’t acclimatized.

The Manaslu Circuit’s altitude profile also adds to the risk. The trekkers start the journey from an elevation point of 870 meters in Machha Khola. Then, they ascend gradually through high-altitude villages with elevations ranging from over 2500 meters to 4000 meters before reaching Larkya La Pass at (5,106 m). The significant level of altitude gain can be draining. In addition, lower oxygen levels at such elevation require proper acclimatization to maintain a good performance. 

While altitude sickness on the Manaslu Trek is a substantial worry a well-designed itinerary with proper acclimatization days can significantly minimize the likelihood. In addition, trekkers should also maintain a steady pace, hydrate themselves be attentive to their bodies to further reduce the possibility. Being well prepared and following preventive measures enhances the safety of the Manaslu Trek allowing you to enjoy every part of the adventure and make precious memories.

Types of Altitude Sickness You May Face During Manaslu Trek 

Acute Mountain Sickness (AMS)

Acute Mountain Sickness (AMS) is the most common kind of risk that trekkers may experience during the Manaslu Trek. This usually occurs when elevation is gained rapidly above 2,500 meters. Some symptoms may arise at a height of approximately 3,000 meters and higher.

The cause of Acute Mountain Sickness is decreased oxygen pressure at higher altitudes and because of this, the trekkers may experience symptoms like headaches, tiredness, nausea, dizziness, difficulty sleeping, and breathlessness. 

Mild Aute Mild Sickness may be managed with rest, proper hydration, and proper acclimatization. If neglected, the symptoms will escalate, making further ascent more risky. Recognizing Acute Mountain Sickness at the initial stage and treating it properly is essential to ensure a smooth and secure journey.

High-Altitude Pulmonary Edema (HAPE)

High-Altitude Pulmonary Edema (HAPE) is a severe and life-threatening disease caused by excess fluid accumulation in the lungs. It generally occurs above 2,500 meters, if the ascent is too rapid. It is an extreme case of altitude sickness and is one of the concerns during high altitude adventures like Manaslu Circuit Trek. 

HAPE usually develops within 2 to 4 days of trekking above 2,500 meters, with symptoms most commonly worsening on the second night. With HAPE’s progression, oxygen shortage increases. 

The trekker can have difficulty walking or thinking, which requires immediate descent to a lower altitude. The signs and symptoms of High-Altitude Pulmonary Edema (HAPE) are as follows:

• Intense Shortness of breath even at rest
• Dry cough (sometimes frothy or bloody sputum)
• Blue Skin, Lips, or Nails
• Chest tightness
• Fatigue
• Faster Heart Rate
• Low Fever

To prevent High-Altitude Pulmonary Edema (HAPE) the trekkers must ensure right acclimatization, gradual climbing, and avoid excessive exertion. 

If HAPE develops, immediate descent is the optimal treatment. Some trekkers may need to be supplemented with oxygen therapy, and in severe cases, the employment of a portable hyperbaric chamber may also be required. Getting medical treatment immediately is required in case of HAPE, as delaying it can be risky and life-threatening. 

High-Altitude Cerebral Edema (HACE)

High-Altitude Cerebral Edema (HACE) is a serious form of altitude sickness where the brain swells from fluid buildup. It generally can occur in patients with Acute Mountain Sickness.  It is an uncommon and rare condition affecting less than 1% of people at altitudes above 4,000 to 5,000 meters. 

However, it is still essential to be careful as you will be in several high-altitude areas during the Manaslu Trek. At higher Himalayan zones, oxygen levels are lower than what your body is used to. So, the brain may react negatively to the lack of oxygen by swelling and can disrupt essential bodily functions.

High Altitude Cerebral Edema Symptoms

• Severe headache
• Confusion
• Loss of coordination
• Dizziness
• Hallucinations
• Fatigue
• Memory Loss
• Seizures
• Slurred Speech
• Disorientation

The effective treatment of High-Altitude Cerebral Edema is going down to a lower altitude, by at least 1,000 meters or lower. Supplemental oxygen or medications like dexamethasone, or acetazolamide can also reduce brain swelling. 

HACE can quickly advance to coma and even death if neglected. Thus, trekkers should be careful about its signs. To avoid this, gradual ascent with proper acclimatization is vital. Early recognition is essential to prevent life-threatening complications.

Factors That Increase the Risk of Altitude Sickness on the Manaslu Trek

Dehydration and Poor Nutrition

Staying hydrated and maintaining proper nutrition is crucial for preventing altitude sickness on the Manaslu Trek. It is one of the most effective methods to prevent altitude sickness risk. The body loses fluids quickly at higher altitudes because of due to higher respiratory demands and dehydration can exacerbate the symptoms of altitude sickness.

At higher zones, the body loses fluids faster. Similarly, when you maintain a diet that is balanced and nutritious. It increases the body’s ability to adapt and reduces the risk of fatigue. An optimal diet rich in nutrients provides the required energy and allows for proper utilization of oxygen which helps in adequate acclimatization.  In addition, you should also refrain from consuming excessive caffeine and alcohol. Thus, you must drink plenty of water while trekking.

Overexertion and Lack of Rest

Pushing the body too hard without adequate rest can obstruct acclimatization. Overexertion can increase the likelihood of altitude sickness, especially during high-altitude adventures like the Manaslu Trek.

Overexertion and rapid ascent without rest can cause faster breathing and heart rates. It can lead to dehydration and exhaustion. Thus, it can be harder for the body to adapt to the higher altitudes. So, trekking at a gradual pace with required breaks is required to maintain energy levels and acclimatize adequately.

Rapid Ascent without Proper Acclimatization

Manaslu Trek takes you to destinations with different altitudes starting from Machha Khola (870 m) to some high-altitude destinations including Samagaon (3,530m), Samdo (3860m), Larkya Phedi (4,460m). In addition, you will cross the exhilarating Larkya La Pass which lies at 5,106 m.

Ascending too quickly on the Manaslu Trek without allowing the body to adapt to decreasing oxygen levels can increase the risk of altitude sickness. Skipping acclimatization days can lead to acute mountain sickness. It can even lead to fatal conditions like high altitude pulmonary or cerebral edema. 

Thus, ensuring a gradual ascent, days of rest and following the exact guidelines for altitude gains on each day can reduce the risk and provide a safer trekking experience to Manaslu.

Individual Susceptibility

The reaction of the body at higher altitudes differs according to the individual. One fact that all trekkers need to consider about altitude sickness is that it is unpredictable and affects various individuals in different manners.  There can be a probability of some trekkers experiencing symptoms even after following proper acclimatization measures.

The previous high altitude exposure, genetics and overall physical fitness levels are some factors that can influence an individual’s ability to adapt to lower oxygen levels. So, it is crucial to watch the symptoms closely. You should be prepared to take the necessary measures. You may descend or get medical help if you happen to experience the symptoms despite taking precautions.

How to Prevent Altitude Sickness on the Manaslu Circuit Trek

Proper Acclimatization Schedule 

A well-planned acclimatization schedule is a must during Manaslu Circuit Trekking. You will require acclimatization days to adapt to the thinner oxygen levels at higher altitudes. On the acclimatization day, trekkers generally take up light altitude ascents and descend back to their designated place of stay which is at a lower altitude to acclimatize successfully. Rapid ascents and not having rest days can lead to overexertion which raises the risk of developing altitude sickness.

During the Manaslu Circuit Trek, generally, the acclimatization days are included in Samagaun (3,530m) and Samdo (3,860m) before navigating the Larkya La Pass (5,106m). Scheduling acclimatization days allows your body to adapt to lower oxygen levels, which reduces the possibility of altitude sickness.

Take care of Hydration & Nutrition 

Proper hydration and nutrition are very necessary during Manaslu Trek. The body loses water at a faster rate at higher altitudes which may lead to dehydration. This can affect the acclimatization process. Thus, consuming sufficient water is necessary to avoid dehydration and maintain overall stamina. 

Likewise, it is advisable to prevent excessive amounts of caffeine and alcohol as they may lead to dehydration. In the same way, nutritious meals are equally essential to avoid fatigue and enhance energy levels which is a must during the Manaslu Circuit Trek. 

Thus, make sure to have high-energy nutrient-rich meals as they can help with acclimatization and enhancing the general stamina which helps you make your way through varied terrains more efficiently and avoid altitude sickness.

Climb High, Sleep Low Strategy

The “climb high, sleep low” strategy involves ascending higher in the day and heading towards lower altitudes at night to sleep. This strategy helps to stimulate red blood cell production in the body and also promotes better oxygen delivery. Ascending higher in the day such as hiking a nearby ridge and heading back to lower altitudes for overnight rest increases the possibilities of a secure journey.

When you make ascends during the day you can adapt to the reduced oxygen levels and when you descend to lower altitudes your body gets additional time to recover and adjust. Following this technique can ensure proper acclimatization and prevent altitude sickness risk.

Medications (Diamox & Alternatives) 

The medications like Acetazolamide (Diamox), help to enhance acclimatization. The medicine can be used as a preventive measure to minimize the risk, the proper acclimatization schedule should also be followed along with it. It is recommended to take the medicine under the supervision of a medical professional. 

They can assess your overall health and suggest a dose that can enhance acclimatization and reduce the likelihood of altitude sickness. Some alternatives include dexamethasone and ibuprofen which also should be under professional guidance. However, generally, Acetazolamide (Diamox), is used as altitude sickness medicine. 

Pacing Yourself: Avoiding Overexertion 

You should trek at a stable pace during high-altitude treks like the Manaslu Circuit. Rapidly ascending and overexertion at higher altitude areas can make you exhausted and accelerate altitude sickness symptoms. Thus, you must pace comfortably, and take frequent breaks which will let the body acclimatize naturally.  

When you rush towards your next destination or try to keep up with faster trekkers can tire you out leading to an increased risk of altitude sickness. Thus, it is crucial to pace yourself and trek comfortably.

Recognizing Early Symptoms 

The detection of early symptoms of altitude sickness is necessary to implement the corrective measures before it gets worse. You should never ignore the warning signals of altitude sickness as it can lead to severe forms like  HAPE and HACE which can be fatal. Thus, it is essential, to carry a pulse oximeter, and take precautionary measures like proper rest, gradual ascent, water, and nutrition intake to reduce the risk. If symptoms occur then you need to head to the lower zones. 

 In addition, hiking with an experienced guide also can be helpful as they are aware of early symptoms and take necessary remedies to minimize the risk.

When to Decide to Descend?

While trekking at high altitude it is necessary to be attentive to the signs of altitude sickness and take preventive measures. If you experience mild symptoms like minor headaches then you may take a rest for a while hydrate thoroughly and wait for some time to observe if your body is adapting or not. 

However, if the symptoms get worse or do not improve with rest, the condition requires treatment  If you experience symptoms like shortness of breath, nausea, confusion, and dizziness and it persists or gets worse, then descending is the best option. If proper precaution is not taken then it may lead to more extreme conditions such as high-altitude cerebral edema (HACE) or high-altitude pulmonary edema (HAPE)

Descending to a lower altitude of at least 500 meters or 1000 meters is an immediate solution and also minimizes risk potential development of other complications that occur because of altitude sickness. If you are uncertain and confused about the symptoms then it is wise to be on the safer side and descend. Likewise, you may take suggestions from expert guides. They are knowledgeable about altitude sickness and can recognize the seriousness or severity and handle the situation better by taking immediate action. Their advice will help a lot in ensuring a convenient and safe journey. 

Altitude adaptation in the body differs from person to person. Thus, it is important to be attentive and take precautionary measures as early as possible. While the descent may hinder your initial plan it can also prevent further health complications and ensure a more secure journey.

Importance of Travel Insurance for Helicopter Evacuation

Travel insurance with a helicopter rescue policy is required while trekking in high-altitude areas such as Manaslu where medical issues like altitude sickness or any kind of illness can arise unexpectedly. Likewise, altitude sickness if not treated sometimes can worsen into serious conditions. The most efficient treatment for such instances is immediate descent. 

However, sometimes it can be difficult for travelers to descend to the lower zones or immediate medical treatment may be required. Many remote trekking regions such as Manaslu have only limited access to health care and medical facilities. Thus, in situations that require immediate descent or medical care helicopter rescue can be the safest and fastest way.

Generally, the cost of such evacuations can be extremely high. So, you should have travel insurance that covers for risks of high-altitude trekking. When you are insured you can trek with peace of mind knowing you are protected financially and covered for cases like altitude sickness or accidents during the trek. For Manaslu Circuit Trek, you must consider insurance that specifically covers helicopter evacuation and ensures that you can be safely evacuated without worrying about the high expenses.

Best Trekking Itinerary of Manaslu Circuit Trek to Minimize Altitude Sickness Risk

An ideal and well-crafted Manaslu Circuit Trek with adequate resting time for acclimatization is essential for a delightful and secure experience. In addition, the itinerary must be crafted to ensure gradual ascents at a comfortable pace. Likewise, a plan for the trek must be made to be flexible and should be modified according to how the body of the individual is acclimatizing, as it is different for each person.

We here at Nepal Guide Treks have designed a standard itinerary of 15 days Manaslu Circuit Trek,  that includes daily altitude gains within safe limits. This allows sufficient time to adjust before ascending further to higher altitudes. 

This is a standard itinerary, including your days of arrival, sightseeing day in Kathmandu, and departure. Your total trekking duration is 10 days, including a day for acclimatization in Samagaun. However, we can also customize it to your fitness level and acclimatization pace.

Standard 15-Day Manaslu Circuit Trek Itinerary with Acclimatization Days

• Day 1: Arrive in Kathmandu (1,400m)
• Day 2: Sightseeing in Kathmandu
• Day 3: Drive to Machha Khola (870 m) from Kathmandu (1,400m)
• Day 4 :Trek to Jagat (1,340 m) from Machha Khola (870 m)
• Day 5 :Trek to Deng (1,860 m) from Jagat (1,340 m)
• Day 6: Trek to Namrung (2,660m) from Deng (1,860 m)
• Day 7:Trek to Shyala (3,500 m) from Namrung (2,660m)
• Day 8: Trek to Samagaon (3,530 m) from Shyala (3,500 m)
• Day 9: Acclimatization Day in Samagaon
• Day 10:Trek to Samdo (3,860m) from Samagaon (3,530 m)
• Day 11 :Trek to Larkya Phedi (4,460m) from Samdo (3,860m)
• Day 12:Trek to Bimthang (3,590 m) via Larkya La Pass (5,106 m)  from Larkya Phedi (4,460m)
• Day 13:Trek to Dharapani (1,860 m) from Bimthang (3,590 m)
• Day 14: Drive back to Kathmandu from Dharapani (1,860m)
• Day 15: Free day in Kathmandu

Staying Safe & Enjoying the Manaslu Circuit Trek

Trekking the Manaslu Circuit is a rewarding and exciting adventure. You will trek through the varied high-altitude terrain, that is remote, wavy, and rugged. In addition, unstable weather conditions also require a good level of physical stamina and well-preparedness. Altitude sickness is also a significant concern that you must consider and manage properly.

The acclimatization pace of every individual is different and one of the important aspects of a safe trek is patience. You need to let your body adjust, hydrate well, and adopt the gentle pace of the Himalayas. Trekking to Manaslu will be a rewarding experience with proper preparation and patience. One of the best tips for a successful trek would be to be attentive to your body. Likewise, you must also follow all precautionary measures suggested by your guides.

Thus, you need to follow an acclimatization schedule properly, nourish yourself with wholesome foods, trek at a gradual and comfortable pace, and carry the required medicines. In addition, you also need to stay adaptable. Likewise, it is also advisable to ensure travel insurance with emergency evacuation coverage for every trekker who is planning to undertake the Manaslu Circuit Trek to take quick action in emergencies. 

Sometimes there can be a change in the weather, or you may need a rest day because of unexpected circumstances, in such cases, flexibility is required. You should trek wisely and develop strategies to cope with the difficulty of a trek to have a delightful and smooth experience. With proper preparation, the Manaslu Circuit will reward you with memories for a lifetime.

Also Read: Annapurna Circuit Altitude Sickness