Trek Guide

Nepal Acclimatization Guide 2026: How to Adjust to High Altitude Safely

How to adjust to high altitude in Nepal safely: how acclimatisation works, the climb-high-sleep-low rule, ascent rates and rest days, how to tell AMS…

By Travel Himalaya Nepal · Jun 6, 2026

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Getting high safely is about acclimatisation, not fitness — a slow, staged ascent is non-negotiable above roughly 2,500–3,000m . Anyone can get altitude sickness, regardless of how fit or experienced they are. Climb high, sleep low. Once you are high, try not…

Travel Himalaya Nepal · News

How acclimatisation actually works

At altitude the air pressure drops, so every breath delivers less oxygen to your blood. Your body responds over hours and days: you breathe faster and deeper, your heart works harder, and over several days you begin producing more red blood cells and…

Travel Himalaya Nepal · News

The rules that keep you safe

Once you are high, keep your sleeping -altitude gain to roughly 300–500m per night. You can walk higher during the day — in fact you should — as long as you come back down to sleep. Build in an acclimatisation day roughly every 1,000m of gain, or every 3–4…

Travel Himalaya Nepal · News

Know the three altitude illnesses — and what to do

Altitude illness is a spectrum. Acute Mountain Sickness (AMS) is common and usually mild. High-Altitude Cerebral Edema (HACE) and High-Altitude Pulmonary Edema (HAPE) are rare but life-threatening, and both are medical emergencies. The single most useful…

Travel Himalaya Nepal · News

Reading your own body

A mild headache or a restless first night at a new altitude can be normal adjustment. Rest, drink water, and — this is the key rule — do not climb higher until it has cleared . What separates a good day from a dangerous one is honesty. Trekkers get into…

Travel Himalaya Nepal · News

Acclimatisation days in practice

On the Everest Base Camp trek , the built-in acclimatisation days at Namche Bazaar (3,440m) and Dingboche (4,410m) exist for exactly this reason. On each, you spend the day hiking to a higher point — the Everest View Hotel above Namche, or the Nangkartshang…

Travel Himalaya Nepal · News

What about Diamox?

Acetazolamide, sold as Diamox, is a medication that can help your body acclimatise and is used by some trekkers as an aid. It is a prescription medicine with real side effects and interactions, so the responsible advice is simple: talk to a doctor before your…

Travel Himalaya Nepal · News

Who is at higher risk

Anyone can develop altitude sickness, but some situations raise the odds and call for extra caution: Fast itineraries. The compressed, budget schedules that promise a big base camp in very few days are the most common cause of trouble. Fewer days means a…

Travel Himalaya Nepal · News

The honest part I have to say

Here is the advice that costs us money, and I will give it anyway because it is true. Never trade an acclimatisation day to save time or cash. The cheapest, shortest itineraries online are cheap and short precisely because they have stripped out the rest days…

Travel Himalaya Nepal · News

The bottom line

Build proper acclimatisation into your plan, ascend slowly, keep the rest days, hydrate and eat, and be honest with yourself about how you feel. Learn the difference between the ordinary discomfort of adjusting and the warning signs that mean go down. Do…

Travel Himalaya Nepal · News

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