What Normal Looks Like at Altitude, Day by Day

The hardest part of altitude on a trek is not knowing whether what you feel is normal. A headache at Dingboche, a bad night at Namche, a breathless climb out of Pheriche: mild altitude sickness is common, usually improves with rest within one to three days, and is managed by not going higher until it passes, while a short list of signs means descend now. This guide walks the Everest Base Camp plan day by day, using the altitudes on our route page, and sets what to expect beside what the NHS and the CDC say is a warning sign. It is general information, not medical advice.

If you are looking for the technical detail on the severe conditions, read HAPE and HACE warning signs. For the rule that shapes the schedule, see the acclimatisation schedule guide.

The baseline: what the health services say

The NHS says altitude sickness usually starts 6 to 10 hours after arriving at a higher altitude, with headache, reduced appetite, nausea or vomiting, tiredness, dizziness and difficulty sleeping. Mild symptoms usually improve within one to three days. The advice is to rest at the same altitude, not to climb higher until you feel better and to tell the people you are with. If symptoms are getting worse or have not improved after a day, descend about 300 to 1,000 m. Descend straight away if symptoms are serious, which means confusion, poor balance or coordination, hallucinations, breathlessness at rest, coughing up frothy or bloody spit, blue or grey lips or skin, or being very drowsy or hard to wake.

The CDC Yellow Book says that above 3,000 m, sleeping altitude should rise by no more than 500 m a night, with an extra acclimatisation night for every 1,000 m gained. Those two numbers are the frame for the rest of this article.

Day by day on the Everest plan

The route page for the Everest Base Camp trek has 12 days, with these sleeping altitudes.

Two of the steps are slightly over 500 m, which the guideline treats as a ceiling; the plan puts rest days at Namche and Dingboche. Individuals differ, and some people need more time.

Days 1 and 2: Lukla, Phakding and Namche

The flight from Kathmandu (about 1,400 m) is quick, and the first night at Phakding (2,610 m) is below the altitude where the 500 m rule starts. You may feel little at all. The climb to Namche is steep for about two hours at the end of day 2. Being breathless on a steep climb is a function of effort and height. A mild headache or a restless first night at 3,440 m is common and not a reason to panic. It is a reason to drink, eat, rest and tell your guide. The rest day at Namche exists for this. A short hike to the Everest View Hotel and back to sleep lower is the plan's way of using it, not a day in bed.

Days 4 and 5: Tengboche and Dingboche

At Tengboche (3,860 m) and especially Dingboche (4,410 m), mild symptoms are most likely to appear, and the NHS onset window of 6 to 10 hours means they often arrive in the evening or overnight. Poor sleep, a dull headache, less appetite and tiredness are the mild list. If you feel like that, do not go on the next morning's climb as planned. Rest or take the acclimatisation day as it comes, and see whether it eases. If it is worse after a day, the NHS advice is to descend about 300 to 1,000 m, which from Dingboche means going back down the valley toward Tengboche.

Day 6: the Dingboche rest day

The plan has a hike up Nangkartshang followed by a night at the same altitude. It is the classic "climb high, sleep low" pattern. If you felt unwell the day before, take the day lower and quieter. If you feel fine, you still do not push on, because a good day at 4,410 m does not change the next night's step.

Days 7 and 8: Lobuche and Gorak Shep

The last two nights are at 4,940 m and 5,164 m. At this height most trekkers are slower and sleep poorly. That does not make a symptom normal if it is getting worse. Breathlessness at rest, a wet cough, confusion, stumbling or unusual drowsiness are on the NHS and CDC lists of serious signs. At Gorak Shep, where there is no village behind the lodges and the walk down to Pheriche (4,371 m) is long, the decision to go down has to be made early. The Himalayan Rescue Association post at Pheriche gives daily talks and can assess you; see our HRA clinics guide.

Day 9: going down

The descent to Pheriche after Kala Patthar (5,545 m) is a relief for most. Headaches ease with lower altitude. If you feel worse on the way down, tell someone: that is not expected and needs checking.

Pace, snacks and the slowest person

Because symptoms tend to arrive in the evening, the way you spend the day matters. Walk at a pace where you can still speak in sentences, take the short days as short days and arrive at the lodge with time to rest before dinner. Eat what you can, even without appetite, and keep drinking. If one person in a group is feeling worse than the others, the group's pace is that person's pace, and the guide's job is to say so out loud so the unwell person is not the one who has to ask. Trekkers who go in a pair or small group often find that the stronger walker needs the rest day just as much, only later. Nothing in the guidance rewards arriving early at a higher lodge. A trek that adds a day to protect the group is working as designed, and a rest day spent reading in a sunny dining room is a good use of the budget, because the permits, flights and guide are already paid for.

The same logic on the Annapurna Circuit

On the Annapurna Circuit the plan goes Chame (2,670 m), Upper Pisang (3,300 m), Ngawal (3,600 m), Manang (3,540 m, rest day), Yak Kharka (4,050 m), Thorong Phedi (4,540 m) and the pass at 5,416 m. The pattern is the same: mild symptoms in the evenings and overnight at Yak Kharka and Thorong Phedi, serious signs mean going down, not up. Going down from Thorong Phedi means Manang; a person who feels ill should not attempt the pass. Our rest days guide covers the placement.

A quick self-check each evening

1. Headache? If yes, rate it, and see whether paracetamol or ibuprofen and rest ease it, as the NHS suggests for symptoms.
2. Appetite and nausea? Loss of appetite is common; vomiting is a sign to take seriously.
3. Sleep? Poor sleep is common at altitude. Ask whether it is getting worse night by night.
4. Balance and thinking? Ask a partner whether you are walking and talking normally.
5. Breathing at rest? If you are breathless sitting still, that is a red flag.
6. Did it improve overnight? The NHS says mild symptoms usually improve in one to three days. If not, stay put or go down.

What to do about it

• Tell your guide or partner at once.
• Rest at the same altitude and do not climb higher until you feel better.
• Drink water and avoid alcohol; the NHS advises both.
• Use simple pain relief for headache if suitable for you.
• Descend 300 to 1,000 m if you are worse or no better after a day.
• Descend immediately for any serious sign.

Medications such as acetazolamide are a topic for a doctor before the trip. They do not change the rules above.

Why honest reporting matters

Most altitude problems become serious when a trekker hides symptoms to keep to a schedule. Partners can help here: ask each other the evening questions out loud. If you are trekking with someone you met through our platform, agree at the start that "I'm not feeling right" is a sentence that can be said without discussion. For more on the partner side, read what to agree with trekking partners before you book.