Trek Guide

Altitude Sickness in Nepal: Prevention, Symptoms & What Actually Works

Altitude sickness stops more Nepal trekkers than bad weather. Here's what actually works — from Diamox to acclimatisation schedules — from guides…

By Travel Himalaya Nepal · Feb 20, 2026

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Altitude sickness — clinically Acute Mountain Sickness, or AMS — is the single most common reason trekkers abandon their Nepal itinerary mid-route. It affects roughly 40% of trekkers who sleep above 3,000 metres , and here is the uncomfortable truth: fitness…

Travel Himalaya Nepal · News

What Is Altitude Sickness?

The umbrella term covers three conditions of increasing severity: Acute Mountain Sickness — the common form. Headache, nausea, fatigue, poor sleep. Unpleasant but rarely dangerous if managed. Onset typically 6–12 hours after reaching a new altitude. High…

Travel Himalaya Nepal · News

Symptoms to Watch For

Mild to moderate AMS: Headache — usually throbbing, worse when bending over or lying flat Nausea or vomiting Dizziness or light-headedness Loss of appetite (the clearest early warning sign in our guides' experience) Disrupted sleep — vivid dreams, frequent…

Travel Himalaya Nepal · News

The Golden Rule

Everything in altitude medicine returns to one principle: if your symptoms are not improving — or are worsening — after 24 hours at the same altitude, descend. Never ascend to sleep higher with unresolved symptoms from the previous day. The classic mistake is…

Travel Himalaya Nepal · News

Acclimatisation Schedules That Work

The standard guideline — above 3,000 m, raise your sleeping elevation by no more than 300–500 m per day, with a rest day every third or fourth day — is the right starting point. But every major route has specific acclimatisation nodes that experienced guides…

Travel Himalaya Nepal · News

Does Diamox (Acetazolamide) Work?

Honest answer: yes, as a preventive measure, and meaningfully so. Acetazolamide stimulates faster, deeper breathing, which raises blood oxygen and speeds the body's natural acclimatisation — compressing the ventilatory adaptation that normally takes three to…

Travel Himalaya Nepal · News

Hydration, Alcohol & Sleep

Three overlooked but critical factors: Water: drink 3–4 litres per day above 3,000 m. Dehydration worsens AMS, and the cold, dry air accelerates fluid loss even when you do not feel thirsty. Urine colour is your guide — aim for pale yellow, not dark amber…

Travel Himalaya Nepal · News

How Our Guides Handle Altitude Emergencies

On routes above 3,500 m, Travel Himalaya Nepal guides carry and use pulse oximeters to track blood-oxygen saturation (SpO₂) as a routine part of each day's check-in. A reading below 80% SpO₂ at rest, or a sharp drop from the previous day's baseline, triggers…

Travel Himalaya Nepal · News

Travel Insurance for Altitude Emergencies

A helicopter evacuation from above 4,000 m in Nepal costs between USD 5,000 and USD 15,000 — and in 2026, top-end rescues above 5,000 m commonly land at the higher end of that range, depending on altitude, weather and the number of flight legs. This is not a…

Travel Himalaya Nepal · News

Frequently Asked Questions

AMS can begin from around 2,500–3,000 m, and risk rises sharply the higher and faster you go. On Nepal's classic treks that means anywhere above Namche on the Everest route or above Chhomrong on the Annapurna route. The trigger is the elevation you sleep at…

Travel Himalaya Nepal · News

Do Not Let AMS Fear Stop You

Altitude sickness is real, common, and deserves respect — but it is not a reason to avoid Nepal's high trails. It is a reason to plan them intelligently. Thousands of trekkers complete Everest Base Camp, Annapurna Base Camp and the Manaslu Circuit every year…

Travel Himalaya Nepal · News

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