Tibet Altitude Sickness: How to Prepare from Singapore, from Lhasa to Everest

In short

Most visitors feel the altitude in Tibet, because you fly straight into Lhasa at about 3,650 metres from close to sea level. Expect a headache, poor sleep and breathlessness on stairs for a day or two. Usually this passes within 12 to 48 hours if you rest and go no higher. To prepare from Singapore, see a doctor at least a few weeks before you fly, ask about acetazolamide (Diamox), rest on your first day and avoid alcohol for 48 hours. Being fit does not protect you. If you become confused, unsteady or breathless at rest, that is an emergency: get oxygen and go down at once. This guide explains how we pace our trips and how to choose one for your comfort. It does not replace medical advice.

Why Tibet hits people from Singapore so quickly

Singapore is at sea level. Most routes reach Lhasa in a single flying day, usually through Chengdu or Chongqing, as our Singapore to Lhasa guide explains. The air in Lhasa holds about two thirds of the oxygen you are used to, and at the Everest visitor area only about half.

Medical guidance is plain about this. The CDC Yellow Book advises against reaching a sleeping height of 2,750 metres in a single day, and above 3,000 metres advises raising your sleeping height by no more than 500 metres a night, with an extra night for every 1,000 metres. The Wilderness Medical Society guideline counts going above 3,500 metres in one day as high risk, even for someone who has never had altitude sickness.

A flight to Lhasa cannot meet that advice, and no tour can change the height of the airport. So everything depends on what you do in the first days and how slowly you go after that.

What altitude sickness feels like

The CDC describes three conditions. It helps to know them apart before you go.

• Acute mountain sickness (AMS): a headache, with at least one of poor appetite, dizziness, tiredness or nausea. It usually starts 2 to 12 hours after arriving, often during or after the first night, and generally clears in 12 to 48 hours if you go no higher. This is the common kind.
• High-altitude cerebral oedema (HACE): confusion, drowsiness or being unable to walk in a straight line. Coma can follow within 24 hours. This is an emergency.
• High-altitude pulmonary oedema (HAPE): a cough, chest congestion, and breathlessness out of proportion to effort or even at rest, worsening over a day or two. This is also an emergency, and it can be fatal faster than HACE.

A simple test on the trip: if you cannot walk heel to toe along a straight line, or you are short of breath while sitting still, tell your guide immediately, day or night.

How high Tibet really is

Heights from our own itineraries, checked on 4 November 2026.

It is how high you sleep that matters most: the CDC notes that oxygen levels are lowest during sleep, and that day trips with an evening back at a lower height are much less stressful for the body. That is why a 5,000-metre pass in the car is far easier than a night at the same height.

Before you leave Singapore

• See your doctor or a travel clinic a few weeks ahead. The CDC says people with coronary artery disease, chronic lung disease, obstructive sleep apnoea or sickle cell trait should get medical advice first. Mention high blood pressure, diabetes or any heart condition too. Tell us about it as well, so we can suggest a gentler trip.
• Ask about acetazolamide (Diamox). It is the medicine best shown to help you acclimatise. The CDC's usual preventive dose for adults is 125 mg twice a day, starting the day before you go up and continuing for the first two days at altitude. Your doctor decides whether it suits you. Try it beforehand if you can: tingling in the fingers and toes is common, and fizzy drinks may taste odd.
• Do not count on fitness. The CDC is clear that training does not lower your risk. Stair climbing in your HDB block or at Bukit Timah still helps, because it makes long days and the Potala's stairs easier.
• Buy the right insurance. Choose a policy that covers high altitude and emergency evacuation, up to at least the height you will reach. Many standard policies have a limit, so check it.
• Pack: paracetamol or ibuprofen for headaches, lip balm, a refillable bottle and warm layers. Nights in Lhasa are cold for most of the year.
• Travel healthy. A heavy cold makes the first days harder. If you fall ill just before departure, call us.

Your first 48 hours in Lhasa

You land at Lhasa Gonggar Airport, about 3,570 metres, and drive for an hour. On our trips the rest of day one is free. The CDC advises only mild exercise for the first 48 hours, so walk slowly and keep your bag light.

• No alcohol for 48 hours, as the CDC advises. Alcohol and sleeping pills should not be used to help you sleep at altitude.
• Eat light and drink normally. Nausea is common at first, so small meals are easier.
• Stay warm, and keep showers short. A long hot shower on the first night can leave you dizzy.
• Use the hotel's oxygen. Our Lhasa hotel, the Lagari, has diffused oxygen, which can help you rest.
• Save the stairs for day two or three. The Potala Palace means long stairways at 3,700 metres, so we leave it until you have had time to adjust, then go slowly with rests.

A mild headache is normal, and paracetamol or ibuprofen usually eases it. A worsening headache with vomiting means you should rest, tell your guide and not go higher.

How our trips pace the altitude

Our trips reach Tibet by different routes and heights, so it is worth choosing with your comfort in mind. All of them begin with two or three nights in Lhasa. For prices, see our Tibet tour cost guide.

• Gentlest: the 7-day Tibet Discovery Tour. You never sleep above about 3,980 metres. You cross the high passes above Yamdrok Lake by car and return to Lhasa, spending your nights in Gyantse and Shigatse.
• Middle: the 8-day Everest Base Camp Tibet Tour. Three nights in Lhasa and one in Shigatse, then a single night near Rongbuk at about 5,000 metres. That last step gains more than 1,100 metres in a day, far more than medical guidance suggests, so expect headaches and poor sleep that night. You are driving down by the next morning.
• A lower start: the 12-day Tibet and Nepal Grand Journey. Three nights in Kathmandu at about 1,400 metres give only a little head start, but you arrive better rested, and the route to Everest is then the same.
• Highest: the 14-day Mount Kailash and Manasarovar Kora. Several nights at about 4,600 metres or more, and a walk over Drolma La at 5,630 metres. This is for experienced, healthy walkers. Your guide carries oxygen and there is a spare day. See our Mount Kailash kora guide.

Comparing Tibet with the Nepal side of Everest? Our guide to Everest Base Camp: Tibet or Nepal side sets out both.

What to do if you feel unwell

The rule from the CDC is simple: never go up to sleep at a higher altitude while you have symptoms.

1. Mild headache or nausea: tell your guide, rest at the same height, take paracetamol or ibuprofen, and stay until you feel better. This usually takes a day or two.
2. Getting worse despite rest: go down. AMS improves quickly with a descent of 300 metres or more. Oxygen at 1 to 2 litres a minute usually eases a headache within about 30 minutes.
3. Confusion, unsteady walking, or breathlessness at rest: this is an emergency. Start oxygen and go down at once, without waiting for morning, and get to a hospital. A doctor may give dexamethasone.

If you need to turn back, your guide changes the plan with you. Missing a night at Everest is disappointing, but it is the right decision, and we would never press anyone to go on.

Oxygen, herbal remedies and other things people ask about

• Small oxygen cans: sold widely in Lhasa, but the CDC notes they hold 5 litres at most, and the guideline says short-term use is unlikely to prevent altitude sickness. They give brief relief. They are no treatment for an emergency.
• Ginkgo and coca products: the guideline does not recommend them for prevention.
• Ibuprofen: good for the headache, and a possible alternative for those who cannot take acetazolamide, though the evidence for prevention is mixed.
• Dexamethasone: a strong medicine for emergencies or high-risk situations, under medical direction. Do not use it to keep going higher.

Who should think twice

• Children: the CDC says they are as likely to be affected as adults, and small children may not be able to tell you how they feel. Ask your paediatrician, and consider a lower destination first.
• Pregnant travellers: the CDC suggests staying below sleeping heights of about 3,050 metres, which rules out Lhasa.
• Heart or lung conditions, or sleep apnoea: get medical advice before booking.
• Anyone who has had HACE or HAPE: the guideline counts you as high risk. Speak to a doctor with altitude experience.
• Older travellers: age alone need not stop you. Many fit older travellers do well, especially on the Discovery Tour's lower route. A medical check matters more than your age.