Sleeping at Altitude: Why It's Hard and How to Sleep Better

Sleeping at altitude is often harder than people expect. On a trek in Nepal, a ski trip overseas or a climb in South America, many people find they wake again and again through the night, feel short of breath, and get up unrefreshed even after hours in bed. This guide covers why altitude disrupts sleep, what periodic breathing is, how sleep changes as you acclimatise, how to sleep better up high, and when poor sleep is a warning sign of altitude sickness.

The short answer: at altitude there is less oxygen, and during sleep your breathing can fall into a cycle of deeper breaths followed by shallow breaths or short pauses, called periodic breathing. That leads to lighter sleep and many brief awakenings. Sleep usually improves as you acclimatise over the first few nights. Ascend gradually, sleep lower than your highest point of the day where possible, and avoid alcohol and sleeping pills. A headache, cough, racing heart or trouble breathing at high altitude needs medical help straight away.

Why altitude disrupts sleep

Altitude sickness can happen above about 2,500 metres, when your body hasn't had time to adjust to the lower amount of oxygen. Healthdirect notes it can be worse at night and can last for days, even if you stay at the same altitude (source).

Even without altitude sickness, sleep changes. A review of high-altitude sleep research describes a strong shift from deeper to lighter sleep stages and a marked increase in brief arousals. People often wake frequently and don't feel refreshed, even when their total sleep time isn't much shorter (source).

What is periodic breathing?

Periodic breathing is the main reason sleep feels so broken up high. The same review describes it as typically three to five deep breaths followed by a couple of very shallow breaths or even a complete pause. During sleep at altitude, carbon dioxide in the blood can drop low enough to switch off the drive to breathe, and breathing restarts only after oxygen falls further (source).

How common is it? A 2023 systematic review found periodic breathing and central apnoeas typically appear with variable severity above 2,000 metres, and above 4,000 metres they are present in practically all people. People report poor sleep quality, insomnia and frequent awakenings with a feeling of suffocation (source).

If your tent mate seems to stop breathing for a few seconds and then takes a few big breaths, this is often what's happening. It can be unsettling to watch or to wake from, but on its own it's a common response to altitude in otherwise healthy people.

Altitude (approximate)	What you might notice
Below 2,000 m	Effects on sleep are usually smaller
2,000 to 2,500 m	Some people notice lighter sleep and periodic breathing
Above 2,500 m	Altitude sickness becomes possible; symptoms can be worse at night
Above 4,000 m	Periodic breathing during sleep in practically everyone

How sleep changes as you acclimatise

The first nights at a new altitude are usually the worst. Research summarised in the review found sleep quality is initially impaired but improves with acclimatisation, along with improved oxygen levels, although periodic breathing can persist (source). The 2023 review notes that much of the early adjustment happens in the first couple of days at a given altitude, though it varies between people (source).

That's why a trek or climb that goes up gradually tends to be kinder to your sleep than flying straight into a high town.

How to sleep better at altitude

Plan the ascent.

1. Go up gradually. Healthdirect advises not going above about 2,500 metres for your first night's sleep, and once above 3,000 metres, not climbing more than 500 metres a day (source).
2. Climb high, sleep low. Spend the night back down below the highest point you reached that day where possible.
3. Build in rest days. Extra nights at the same altitude give your breathing and sleep time to settle.

Look after the basics.

• Skip alcohol and sleeping pills. Healthdirect advises against both at altitude because they interfere with the way your body adapts (source). See does alcohol help you sleep.
• Stay warm. Mountain nights are cold. Use a sleeping bag rated for the conditions, a beanie and dry socks, and keep tomorrow's clothes in the bag with you.
• Get comfortable. Some people find a rolled jacket under the head more comfortable than lying completely flat.
• Bring an eye mask and earplugs for shared huts, teahouses and tents. See silent alarms for camping.
• Keep a steady routine for meals and bedtime, especially if you've also crossed time zones. See jet lag tips.
• Talk to your GP before the trip. Healthdirect notes doctors may prescribe medicines to help you adjust, particularly if you've had altitude sickness before (source).

Early starts. Summit days and sunrise viewpoints often start in the dark. Lay out your gear the night before so you can get moving quickly in the cold. See sunrise hike wake-up tips.

When poor sleep is a warning sign

Broken sleep alone is common at altitude. But some symptoms mean you need help immediately. Healthdirect lists headache, cough, a racing heart and trouble breathing as symptoms that need urgent medical help if they happen at high altitude, alongside dizziness, weakness and nausea (source).

• Don't go higher with symptoms. Tell your guide or group.
• Descend if symptoms get worse or don't improve.
• Watch each other at night, especially for severe breathlessness at rest or trouble waking.

If you already have a sleep or breathing condition, the 2023 review found altitude can make obstructive sleep apnoea worse (source). If you use CPAP or have signs of sleep apnoea, talk to your GP or sleep specialist well before you travel. This guide is general information, not medical advice.

Where the Sovune Nudge fits

We make the Sovune Nudge, a silent alarm wristband, so we're not neutral. It won't change how you sleep at altitude, but in a shared tent or teahouse dorm before a dark start, a quiet alarm on your wrist is useful.

• Silent, so it wakes you without waking your tent mate or the rest of the hut.
• Up to 14 days of nightly use per charge, handy where power is limited.
• No app, phone or Bluetooth, so your phone battery is saved for photos and maps.
• Water-resistant for everyday use, so rain is fine (not swimming or diving).
• Escalating vibration for a full minute, building from a gentle tap through three intensity levels.

It comes with a 30-day money-back guarantee.

Quick answers

Why can't I sleep at high altitude? Lower oxygen causes periodic breathing during sleep, which leads to lighter sleep and frequent brief awakenings.

Does sleep at altitude get better? Usually, yes. Sleep quality tends to improve as you acclimatise over the first few nights, though some periodic breathing may continue.

Can I take a sleeping pill at altitude? Healthdirect advises against sedatives and sleeping pills at high altitude because they interfere with how your body adapts. Ask your GP before you travel.

Is waking up gasping at altitude normal? It's common with periodic breathing. But breathlessness at rest, a headache, cough or racing heart needs urgent medical help.

For every type of silent alarm compared, see our complete guide to vibrating alarms in Australia.

See the Sovune Nudge →