Getting altitude sickness in Nepal is quite common. Studies in Nepal’s high mountain regions show that between 30% and 50% of trekkers experience symptoms of acute mountain sickness in Nepal. On the Annapurna Circuit, a recent study found an incidence of 45%. In the Everest region, the figure sits around 30%. So if you are heading above 2,500 metres, the chances are real.

What is altitude sickness?

Altitude sickness happens when your body does not get enough oxygen at high altitude. The air contains the same percentage of oxygen as at sea level, but the air pressure is lower. Your lungs take in less oxygen with each breath. Your body needs time to adjust, and that process is called acclimatisation.

Altitude sickness comes in three forms:

1. Acute Mountain Sickness (AMS) The mild form. The symptoms feel a lot like a hangover: headache, nausea, fatigue, loss of appetite, trouble sleeping. Some people barely notice it. Others feel awful. Either way, AMS is a warning sign. Your body is telling you it needs more time.
2. High Altitude Pulmonary Edema (HAPE) A life-threatening condition. Fluid builds up in the lungs. The symptoms are a cough (wet or dry), shortness of breath even at rest, and all the symptoms of AMS. Descend immediately and seek medical help.
3. High Altitude Cerebral Edema (HACE) Also life-threatening. The brain swells. The symptoms are stumbling or losing balance (ataxia), confusion, drowsiness or strange behaviour. Descend immediately and seek medical help.

For all three, the same rule applies: descent is the best medicine.

How we approach altitude on our treks

Every trek we design above 2,500 metres is built around one principle: give your body time. That is not just our preference, that is what the research shows. A recent study at the Himalayan Rescue Association aid post in Manang found that almost a third of altitude sickness patients had ascended too quickly, more than 500 metres per day above 2,500 metres.

So this is what we do at By Mountain People:

• Acclimatisation days are built into the itinerary. On our higher-altitude treks, you will have rest days at strategic points. These are not lazy days. They are part of your body’s training. You stay at altitude, walk a little higher during the day, and sleep lower. That is how your body adapts.
• Maximum 500 metres ascent per sleeping altitude per day above 2,500 metres. This is the international guideline, and we stick to it. Some routes ask for creativity to make this work, and that is exactly what your guide does.
• Daily check-ins between you and your guide. Your guide is experienced and watches closely, but your guide cannot feel what you feel. Honest, daily communication between you and your guide is one of the most important safety tools we have. How is your headache today? How did you sleep? How is your appetite? These are not small talk questions. They are the moments where we catch something early.
• A team that knows what to do. Our guides are trained to recognise the signs of AMS, HAPE and HACE. They carry first aid supplies. They know which guesthouses to head to, which routes to descend, and when to call for evacuation. Govinda has guided on these routes for over a decade. He has seen it all, and he has trained the team accordingly.

A small story from Valerie

Acute mountain sickness in Nepal is no joke. On my first trek up there, I lost my appetite as we gained altitude. I knew about staying hydrated, but I never heard about eating. I started sharing meals with my best friend, and we thought we were just not very hungry.

Later I learned that loss of appetite is one of the early signs of altitude sickness. I was lucky. Nothing serious happened. But ever since, I make myself eat full portions. Even when I do not feel like it. My body is working hard up there, walking long days, staying warm, processing the altitude. It needs fuel. 🔥

That is why we tell every one of you the same thing: do not skip meals. If the portions feel too big, eat soup and small snacks in between. But keep eating.

What you can do yourself

Your guide and your team take care of a lot. But your body is yours, and there are things only you can do.

• Drink plenty of water. Aim for three to four litres per day at altitude. Your body loses more water through breathing in the dry mountain air than you might think.
• Avoid alcohol and limit coffee. Both are diuretic, which means they make you urinate more and dehydrate faster. Alcohol also masks the symptoms of altitude sickness, which is dangerous when you need to read your body clearly.
• Eat three meals a day, plus snacks. As my story shows, your appetite may drop. Eat anyway.
• Tell your guide how you feel. Honestly. This is the single most important thing. Some travellers downplay symptoms because they want to keep going. Please do not. Your guide cannot help you if you do not tell them what is going on.
• Sleep low, climb high. On acclimatisation days, walk to a higher point during the day, then return to sleep at a lower altitude. Your body adapts faster this way.

What about Diamox?

Diamox, also known as acetazolamide, is a medication that helps your body acclimatise faster. It is widely used and well researched.

However, at By Mountain People we do not advise taking Diamox preventively. Because we believe it is important to feel how your body responds to altitude, rather than masking the early signs. If you suppress symptoms preventively, you may miss a warning that something is wrong.

That said, we do recommend bringing Diamox with you on higher-altitude treks. It can be useful to have on hand if descending immediately is not possible, or if symptoms develop and your doctor or guide advises you to take it. Talk to your GP or travel doctor before your trip about what to bring and when to use it.

Walk safely, return safely

Altitude is part of what makes Nepal so extraordinary. But you don’t want to get altitude sickness in Nepal. The Himalayas may not be gentle, but they are honest. They reward travellers who pay attention, who listen to their bodies, and who walk with people who know the way.

We have built our treks around exactly that. Acclimatisation days that are not negotiable. Daily distances that fit what your body can handle. Guides who notice things before you do. And a team that has been doing this for over a decade.

If you want to know more about altitude or about a specific trek, just ask. You can reach us by email, meet us at a travel fair, or get in touch through our [contact page]. We are happy to talk it through.

Reliable sources for more information

• Himalayan Rescue Association — non-profit operating high-altitude aid posts in Pheriche and Manang, with decades of experience in altitude illness.
• UIAA Medical Commission — international mountaineering federation with detailed medical advice.
• Wilderness Medical Society Practice Guidelines — evidence-based clinical guidelines on the prevention and treatment of altitude illness.

Disclaimer: This blog provides general information and is based on our experience and on the sources listed above. It is not a substitute for medical advice. If you have questions or concerns about altitude sickness, please contact your GP or a travel doctor before your trip.

Helicopter Rescue Nepal: How to Avoid It on Your Trek?

If you’re planning a trek in Nepal, this is something worth knowing. Helicopter rescues happen every trekking season, and not always for the right reasons. If you search online on “helicopter rescue Nepal” you’ll find numerous news articles about early 2026, when nine people were arrested in Nepal for faking helicopter rescues. But the real story goes deeper than the scam itself.

In many cases, an unnecessary evacuation doesn’t start with fraud. It starts with poor planning.

How do fake helicopter rescues actually start?

Large groups with only one guide, or climbing to high altitude too fast. Unrealistic itineraries that don’t allow enough time to acclimatise. Groups eating at lodges where hygiene is insufficient, or ordering dishes you simply shouldn’t eat in remote areas. Meat, for example, is often transported on foot to high-altitude lodges, without refrigeration. The risks are real.

The ratio of guides to trekkers matters too. A single guide responsible for a large group cannot monitor everyone closely enough at altitude. When something goes wrong, the pressure to act fast, rather than act right, increases significantly.

When things go wrong in these situations, guides often have only one option: call a helicopter. And that’s where it gets complicated. Some travel organisations own their own helicopters and clinics, and profit directly from every evacuation. In some cases, the rescue wasn’t even necessary in the first place.

One more thing worth knowing: many international travel organisations don’t run their own trips at all. They sell the journey, but hand the execution over to a local operator. And the lines of responsibility become blurred.

How to protect yourself

There are 5 things you can do:

1. Know the symptoms of Acute Mountain Sickness (AMS). It develops gradually as you gain altitude. It doesn’t suddenly hit you after a meal. Symptoms include headache, nausea, dizziness and fatigue. If you recognise them early and communicate with your guide, the solution is usually simple: rest, hydrate, or descend slightly.
2. Choose your organisation carefully, and check whether the local travel company executing your trip is registered with TAAN (Trekking Agencies’ Association of Nepal). TAAN sets minimum standards for licensed guides, safety protocols and responsible trekking practices. Registration is not a guarantee, but its absence is a red flag.
3. Ask whether your guide holds an official trekking license.
4. Look for verifiable reviews. Not just on their own website, but especially on independent platforms.
5. Pay attention to how the organisation communicates. A reliable company has no trouble answering specific questions about safety, emergency protocols and what happens when the weather turns.

It’s also important to check your insurance. Not all travel insurance policies cover trekking in Nepal. Some offer limited coverage at higher altitude or in remote areas. Check your policy before you leave, and make sure it explicitly covers high-altitude trekking and emergency evacuation in Nepal.

Most policies define high altitude as above 4,000 or 5,000 metres. Some exclude helicopter evacuation unless it is deemed medically necessary by a certified professional on the ground. Read the fine print before you leave, not after something goes wrong.

How By Mountain People prevents helicopter rescues in Nepal

By Mountain People is both a local Nepali and a registered Dutch travel company, connected to VvKR (Association of Small-scale Travel Specialists, Vereniging van Kleinschalige Reisorganisaties) and backed by the guarantee fund VZR Garant. That means you have the security of a recognized European travel organisation, combined with the local knowledge and network of a team that has been working in these mountains for years.

We don’t outsource. We have our own execution team in Nepal, are registered at TAAN, with guides and porters we know personally, work with for years and trust completely. Short lines, high standards.

With By Mountain People, you either trek with your own private guide, or join one of our small groups. The group trips are never more than 10 people, and always with two guides when groups are larger. Our itineraries are built around proper acclimatisation, not speed. Before you head into the mountains, your guide checks your gear, briefs you on food safety and makes sure you know what to expect.

The real test comes when things don’t go as planned

In October 2025, an unexpected storm hit the Himalayas in the middle of peak season. Entire areas were closed, flights delayed, rescue teams deployed. At By Mountain People, we had several groups out on the trails at the time. And every single person was brought to safety. Some returned to Kathmandu or Pokhara, others completed their trek via an adjusted route.

Not one of our groups needed a helicopter evacuation. Not during the storm, and not at any point during the rest of 2025.

Trekking safely in Nepal: the bigger picture

These scams damage the reputation of an entire industry, one that is largely built on honest, hard-working people. The guides who get up before dawn. The porters who carry heavy loads at altitude. The teahouse owners who open their doors to strangers every single day. They deserve better than to be associated with the actions of a dishonest few.

Nepal remains one of the most beautiful trekking destinations in the world. Go well prepared, choose wisely, and you’ll have nothing to worry about.

Curious about how we work? We’d love to tell you more.

Or read more about trekking in Nepal or learn how to recognise and prevent altitude sickness on your trek.