Last verified October 2026 against the NHS, the CDC Yellow Book and the Leh district permit portal. Health guidance changes, and this page is general information, not medical advice. Talk to a doctor or travel clinic before you go, especially if you have a heart, lung or blood condition.
Most places in India let you land and start sightseeing the same afternoon. Leh does not. A short flight takes you from Delhi, at roughly 215 m, to a town at about 3,500 m, and your body has had no time to adjust. The CDC Yellow Book says rates of altitude illness approach 50% when travelers go straight to heights like this without staging the climb. Plenty of those cases are a bad headache and a lost appetite. A few are not.
This guide explains what altitude sickness in Ladakh looks like, how to pace the first days, what the health agencies say about medication, and when to stop and go down. It pairs with our Ladakh and Spiti acclimatization planner, which checks a night-by-night plan against the same guideline, and the Ladakh destination guide covers routes and places. For the wider health picture, see the India vaccinations and health prep guide.
Why is Leh harder than most Indian destinations?
Two things stack up: height and speed. The NHS says you can get altitude sickness above about 2,500 m, and that you are more likely to if you reach that height quickly. The CDC sorts trips by the altitude of your first night. Anything above 3,400 m on day one falls in its high-risk category, assuming you start below 1,200 m. Leh, at around 3,500 m, is just over that line, and arriving by air from Delhi means you start well below it.
The rule most travel-medicine sources work from is simple. Once you sleep above 3,000 m, raise your sleeping altitude by no more than about 500 m a night, and add an extra night for every 1,000 m you gain. The CDC attributes this to the Wilderness Medical Society. Run Ladakh through that rule and the awkward spots show up quickly.
| Move | Approximate change in sleeping height | Fits the 500 m guideline? |
|---|---|---|
| Delhi (about 215 m) to Leh (about 3,500 m) | Up about 3,300 m in one day | No. This is why the first two days matter most |
| Leh to Nubra Valley | Lower than Leh (Nubra villages are commonly given as roughly 3,000 to 3,100 m) | Yes, it is a step down |
| Leh to Pangong Lake (about 4,225 m) | Up about 700 m | Slightly over. Do Nubra first, or add a night in Leh |
| Leh to Tso Moriri (about 4,500 m) | Up about 1,000 m | No. Plan an extra acclimatization night |
Altitudes are approximate and tourism sources differ by tens of metres, so treat the table as a planning aid, not a survey. The arithmetic is ours, applied to the guideline the CDC and NHS publish. High passes you only cross during the day matter less than where you sleep, because the CDC notes oxygen levels fall furthest during sleep and that day trips with an evening return to lower ground are much less stressful.
What does altitude sickness feel like?
The CDC compares acute mountain sickness (AMS) to an alcohol hangover. Headache is the main symptom, often with dizziness, tiredness, poor appetite or nausea. The NHS lists difficulty sleeping as well. Onset is usually within hours: the NHS says 6 to 10 hours after arriving, the CDC says 2 to 12 hours, often during or after the first night.
Mild cases usually settle in one to three days if you stay at the same height and rest. The CDC adds a useful point: symptoms that begin after three days at the same altitude, with no further climb, should not be put down to AMS. Look for another cause, such as dehydration or a stomach bug. Our street food safety guide covers the second one.
The serious forms are rare below 4,300 m but worth knowing. High altitude cerebral edema (HACE) shows up as confusion, poor balance or unusual drowsiness. High altitude pulmonary edema (HAPE) starts with a cough, chest congestion and breathlessness that is out of proportion to effort. Both are emergencies.
What should the first 48 hours in Leh look like?
The Leh district administration, which runs the permit portal, advises at least 48 hours of acclimatization on arrival. The CDC gives the same figure for avoiding alcohol and hard exercise. Treat the first two days as a fixed part of the trip, not spare time.
- Book a hotel that lets you check in early or hold your bags, and go to bed or sit down when you arrive. Your first afternoon is for resting.
- Drink water steadily. The NHS lists enough fluids as a basic precaution.
- Skip alcohol for the first 48 hours. The CDC says alcohol and other respiratory depressants should be avoided, and that includes using them to get to sleep.
- Keep exercise gentle. A slow walk around the town is fine; a long climb to a monastery on day one is not.
- If you normally drink coffee or tea, keep doing so. The CDC points out that a caffeine-withdrawal headache can be mistaken for altitude illness.
- Expect broken sleep. Above about 2,700 m, the CDC says periodic breathing is nearly universal, so waking at night is common and not itself a warning sign.
- Do not go higher to sleep while you have symptoms, however mild. This is one of the CDC’s three core safety rules.
How should you order a Ladakh itinerary?
The usual mistake is a fast circuit: land, drive over a 5,000 m pass the next morning, sleep at a lake. Give the body a lower step first. A sensible shape is two or three nights in Leh, then Nubra Valley, which sits lower, then a higher night at Pangong. If Tso Moriri is on your list, it comes last, with a spare night built in.
Arriving by road from Manali or Srinagar is a different problem. It spreads the climb over several days, which helps, but those routes cross very high passes and some overnight camps sit above 4,000 m. The same sleeping-altitude rule still applies, so check each night on the planner rather than assuming the road is gentler. Dates matter too: the high passes are snowbound for part of the year, and our monsoon travel guide and best time to visit India page explain why Ladakh is a summer destination.
Tight on days? Cut a place, not the acclimatization nights. Lay out the options in the India itinerary planner and run the result through the acclimatization planner before you book anything non-refundable. The same pacing applies to Spiti and to the higher parts of North Sikkim.
What about medication?
This is a decision for a doctor, and we do not give doses. What the agencies say is useful background for that conversation. The NHS advises seeing a GP or travel clinic if you have had altitude sickness before or are going high quickly, because they may prescribe preventive medicine. The CDC Yellow Book tells clinicians that for travelers whose first night is above 3,400 m, with rates of illness approaching 50%, a low threshold for acetazolamide is advised.
Acetazolamide is the drug most often discussed. The CDC says it speeds acclimatization, and the Wilderness Medical Society calls it the preferred preventive medicine. It is a sulfonamide derivative with its own side effects, including tingling in the fingers and a change in how fizzy drinks taste. People with a history of anaphylaxis or multiple drug allergies need extra caution. Dexamethasone is a prescription treatment for moderate to severe illness, not something to buy for fun, and the CDC says ibuprofen can also help prevent AMS though not as well as acetazolamide.
Practical point: sort this out at home. You want a prescription and an informed conversation before you land, not a search for a pharmacy at 3,500 m with a headache.
Which common fixes do not work?
- Being fit. The CDC states that training and physical fitness do not affect the risk of altitude illness. Marathon runners get it. So do children, who are as susceptible as adults.
- Canned oxygen. The CDC says the small handheld cans hold at most about 5 litres of oxygen, which gives brief relief but not sustained improvement. Do not treat one as a plan.
- Pushing through. The CDC calls the first rule recognising the early symptoms and admitting you have them. Hiding a headache from your group is how mild cases become bad ones.
- Sleeping pills and alcohol. The CDC says respiratory depressants should not be used to help you sleep at altitude.
A pulse oximeter is the one gadget that can help. The CDC notes they cost little and can show how acclimatization is going. At about 3,050 m, it says, oxygen saturation in a healthy person can fall to roughly 88 to 91%. A number alone does not diagnose anything, so use it alongside how you feel.
When should you descend or get help?
If symptoms are mild, rest at the same height and do not climb. The NHS says to go down by around 300 to 1,000 m if symptoms worsen or do not improve after one day. The CDC adds that AMS typically improves rapidly with a descent of 300 m or more.
Get medical help at once, and descend if you can, when someone at altitude:
- is confused, or has problems with balance or coordination
- sees or hears things that are not there
- is short of breath even at rest
- has a cough, or coughs up frothy or bloody spit
- has blue or grey skin, lips, tongue or nails
- is very sleepy or hard to wake
In Ladakh, descending usually means a drive or a flight out of Leh, so decide early. Tell your driver and guesthouse that you feel unwell. Ask for help before nightfall, not after.
How do permits and insurance fit in?
Permit rules for areas such as Pangong, Nubra and Tso Moriri are handled by the Leh district administration through an online portal, where the fee is paid online. Its notice says the fee covers the environmental fee, the Red Cross fund and the wildlife fee. We could not confirm current amounts or the exact rules for US and UK passport holders from an official page this month, so we have left them out. Check the official Leh permit portal for your nationality before you travel.
On insurance, read the altitude clause. Some policies exclude cover above a stated height or want an add-on, and evacuation from a remote area is where cover earns its keep. Our India travel insurance guide lists what to check. Pack for cold nights and strong sun too; the India packing list helps.
Who should talk to a doctor first or rethink the trip?
The CDC lists medical conditions that call for caution or a specialist opinion before high-altitude travel. These include unstable angina, poorly controlled asthma, severe chronic lung disease, decompensated heart failure, and a heart attack or stroke in the previous 90 days. People with sickle cell disease or severe sleep apnea are also on the list. Stable, well-controlled conditions such as mild asthma or controlled high blood pressure are generally not barred, but you should still have a plan.
For pregnancy, the CDC suggests clinicians may prudently advise against sleeping above about 3,050 m, which rules out Leh as a base for most pregnant visitors. Anyone in these groups should get individual advice from a doctor who knows altitude medicine. If you are weighing the whole trip, our guide to travel safety in India covers the non-medical side.
Common mistakes
- Booking a pass crossing or lake night for day two because the tour company runs it that way.
- Treating the planner or any guide as a substitute for a doctor.
- Drinking on the first night because the flight was long.
- Ignoring a headache to avoid delaying the group.
- Relying on a single oximeter reading in place of symptoms.
- Buying a non-refundable itinerary with no spare day for weather or illness.
Frequently asked questions
How long does it take to acclimatize in Leh?
The CDC says the acute adjustment happens over the first 3 to 5 days, and Leh district advises at least 48 hours of acclimatization on arrival. Mild AMS typically resolves in 12 to 48 hours if you do not climb higher.
Do I need Diamox for Ladakh?
That is a decision for your doctor. The CDC advises clinicians to have a low threshold for acetazolamide when travelers reach heights above 3,400 m without staged acclimatization, and the NHS says to see a GP or travel clinic if you are going high quickly.
Can I fly straight to Leh?
Many visitors do. The NHS says to avoid flying directly to a high-altitude place and, if you cannot, to rest for a day before going higher. In practice that means a quiet first day and no pass crossings.
Does being fit reduce the risk of altitude sickness?
No. The CDC says training and physical fitness do not affect the risk. How fast you climb and where you sleep matter far more.
Do handheld oxygen cans work?
They give brief relief at most. The CDC says the small cans contain too little oxygen, about 5 litres at most, for sustained improvement, so they are not a substitute for resting or descending.
What should I do if my travel companion becomes confused or breathless?
Treat it as an emergency. The NHS says to get medical help immediately and go to a lower altitude straight away, around 300 to 1,000 m lower if you can. Do not leave the person alone.