Safety
Altitude Sickness in the High Himalayas: Prevention That Works
Most altitude problems on Himalayan road trips come from gaining height too fast, not from being unfit. Here is the acclimatisation logic we build into every itinerary.
Acute Mountain Sickness is a plumbing problem, not a fitness problem. Marathon runners get it; sedentary travellers sometimes do not. What reliably predicts it is how quickly you gained altitude and how well you slept and hydrated on the way up.
The numbers that matter
- Above 2,500m, symptoms become possible.
- Above 3,500m, they become common if you ascended in a single day.
- Sleeping altitude is what counts — a day trip to 5,000m is far safer than a night at 4,500m.
- Aim to raise sleeping altitude by no more than 500m per night above 3,000m.
Symptoms, in order of seriousness
Mild AMS looks like a hangover: headache, nausea, poor appetite, broken sleep. It is common and usually resolves with a rest day. What is not normal is breathlessness at rest, a wet cough, confusion, or loss of coordination. Those point to HAPE or HACE, and the only treatment is immediate descent.
Never climb higher with symptoms you did not have yesterday, and never sleep higher with a headache that will not clear.
What we build into itineraries
- 01A staged approach: no itinerary jumps straight to 4,000m on day one.
- 02A dedicated acclimatisation day before the first pass above 5,000m.
- 03Day trips high, nights lower, wherever the route allows.
- 04Oxygen and a pulse oximeter in the convoy, and drivers trained to read them.
Practical prevention
- Three to four litres of water a day. Dry high-altitude air removes far more than you notice.
- No alcohol for the first 48 hours, and go easy on sleeping tablets.
- Eat carbohydrate-heavy food even when appetite disappears.
- Discuss acetazolamide with your doctor before the trip if you have a history of AMS.
- Tell the crew early. Every serious incident in the mountains starts with someone staying quiet.
Who should be extra careful
Anyone with uncontrolled hypertension, significant heart or lung disease, or a previous episode of HAPE should get medical clearance first. Pregnancy and recent respiratory infections are also reasons to talk to a doctor before booking a route that sleeps above 4,000m.
Frequently asked
- How long does it take to acclimatise in Ladakh?
- Most people need 48 hours at around 3,500m before moving higher. Our Ladakh and Trans Himalayan itineraries build in that rest before any pass above 5,000m.
- Does being fit prevent altitude sickness?
- No. Fitness does not protect against AMS, and fit travellers often ascend faster, which increases the risk. Ascent rate, hydration and sleep matter far more.
- Do you carry oxygen on expeditions?
- Yes. Every convoy carries supplemental oxygen and a pulse oximeter, and our drivers are briefed on symptom recognition and descent protocol.
- What is the fastest way to treat altitude sickness?
- Descent. Dropping 500 to 1,000m in sleeping altitude resolves most cases quickly. Oxygen and rest help, but they are not a substitute for going down when symptoms worsen.
Written by
Hello Himalayas Expedition Desk
Route planning & operations, Rohru
The crew that scouts, drives and runs every Hello Himalayas convoy across Spiti, Ladakh and Zanskar. Everything here comes from seasons spent on the road, not from a desk.