Trek Guide
Complete guide to acute mountain sickness (AMS) in Nepal — how to recognise HACE and HAPE, Diamox dosage, acclimatisation schedule, when to descend…
By Travel Himalaya Nepal · Jun 14, 2026
Altitude sickness affects roughly one in three trekkers in Nepal, and every year it sends unprepared hikers down in helicopters — or worse. The good news: acute mountain sickness (AMS) is almost entirely preventable if you ascend slowly, recognise early…
Travel Himalaya Nepal · News
AMS can begin as low as 2,500 m (8,200 ft) — Namche Bazaar sits at 3,440 m The golden rule: above 3,000 m, ascend no more than 300–500 m of sleeping altitude per day Diamox (acetazolamide) 125–250 mg twice daily is the standard prophylactic in Nepal HACE and…
Travel Himalaya Nepal · News
When you ascend rapidly, the partial pressure of oxygen in the air drops. Your body has not had time to produce extra red blood cells or adapt its breathing pattern, so your tissues become mildly hypoxic. The result is AMS — a spectrum of symptoms that ranges…
Travel Himalaya Nepal · News
Travel Himalaya Nepal · News
AMS is the mildest and most common form. Symptoms typically appear within 6–12 hours of arriving at a new altitude and include: Headache — the cardinal symptom; usually frontal and throbbing Nausea or vomiting Fatigue and weakness out of proportion to effort…
Travel Himalaya Nepal · News
HACE is the brain swelling with fluid. It is a medical emergency. Signs that AMS has progressed to HACE include: Severe, worsening headache that does not respond to ibuprofen Ataxia — have the person walk heel-to-toe in a straight line; staggering is a red…
Travel Himalaya Nepal · News
HAPE is fluid accumulating in the lungs. It is the leading cause of altitude-related death, and it can develop without preceding AMS. Warning signs: Breathlessness at rest — not just on exertion A persistent cough, often productive with pink or frothy sputum…
Travel Himalaya Nepal · News
No drug replaces proper acclimatisation. The principle is straightforward: ascend gradually, build in rest days, and follow the maxim "climb high, sleep low." On the Everest Base Camp trek , the standard safe schedule includes: Two nights in Namche Bazaar…
Travel Himalaya Nepal · News
Acetazolamide (brand name Diamox) is a carbonic anhydrase inhibitor that speeds up your breathing rate, increasing blood oxygen saturation at altitude. It is the only drug with robust evidence for both prevention and treatment of AMS. Standard prophylactic…
Travel Himalaya Nepal · News
Dehydration worsens the symptoms of AMS. At altitude, your respiratory rate increases and you lose water rapidly through breathing — often without feeling thirsty. Aim for 3–4 litres of fluid per day above 3,500 m. Signs your urine should be pale…
Travel Himalaya Nepal · News
A pulse oximeter clips to your fingertip and reads your blood oxygen saturation (SpO2) and pulse rate. It is one of the most useful tools you can carry in Nepal's high country, available for USD 8–15 in Namche Bazaar or Lukla. Typical SpO2 values at altitude…
Travel Himalaya Nepal · News
The rule is simple: never ascend with symptoms of AMS; always descend with symptoms of HACE or HAPE. Descending even 300–500 m can produce rapid improvement. Do not wait until morning. Do not let a trekker with HACE or HAPE sleep at the same altitude "to see…
Travel Himalaya Nepal · News
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