When you're sick, get at least your normal amount of sleep, which is 7 to 9 hours for most adults, and more if your body asks for it. There's no official "sick day" number. Sleeping 9 or 10 hours, plus a nap or two, is normal while you're fighting off a cold or the flu. Rest is part of how your body recovers, so this isn't the week to cut corners.
Free toolSleep Needs by AgeRecommended hours for every age, from newborns to over-65s.How many hours of sleep do you need when sick?
Start with your usual recommended amount and treat it as the minimum. Sleep experts recommend 7 or more hours for adults, and a consensus panel from the American Academy of Sleep Medicine noted that sleeping more than 9 hours can be appropriate for people who are recovering from illness.
This is a rough guide for adults, not a prescription:
| How you feel | Sleep to aim for |
|---|---|
| Healthy, normal day | 7 to 9 hours |
| Mild cold, still up and about | 7 to 9 hours, with an earlier bedtime |
| Flu or fever, first few days | As much as your body wants, often 9+ hours plus naps |
| On the mend | Gradually back to your normal 7 to 9 hours |
Children and teens need more sleep than adults to begin with. Find your own baseline by age with the how much sleep do I need calculator. For babies and young children who are ill, follow your pediatrician's advice.
Why you feel so sleepy when you're sick
That heavy, can't-keep-my-eyes-open feeling is your immune system at work. When your body fights an infection, it launches an inflammatory response, and the signaling molecules involved also act on the brain. A major review of sleep and immunity describes how this response can increase how long and how deeply you sleep. It can also disrupt sleep, which is why a fever or cough can leave you tossing and turning.
Researchers think the extra sleep during infection helps your defenses. The same review notes that sleep is linked to a lower risk of infection and can improve how well people respond to infections and vaccines. So when you feel the pull to sleep, it's reasonable to follow it.
Does sleep help you get better faster?
Research suggests it helps, though the strongest evidence is about sleep before you get sick. In one study, researchers measured people's sleep with wrist trackers for a week, then exposed them to a cold virus. People who slept less than 5 hours a night were about 4.5 times as likely to develop a cold as those who slept more than 7 hours. Those sleeping 5 to 6 hours were about 4.2 times as likely.
There's less direct research on exactly how much extra sleep speeds recovery once you're already ill. But nothing suggests that fighting your sleepiness helps, and being short on sleep makes everything, from mood to focus, feel worse.
How long should you nap when sick?
When you're sick, nap as long as you need to feel rested. The usual advice to keep naps short and early is for healthy days. While you're ill, extra rest matters more than protecting a perfect schedule.
A few tips keep daytime sleep from wrecking your nights:
- Nap earlier in the day when you can. A long nap at 6 PM is more likely to leave you wide awake at bedtime.
- Keep a rough wake-up time. Even when sick, getting up at a similar time helps your body clock stay on track.
- Rest counts too. Lying down with your eyes closed, or on the couch with a show, still helps you recover.
If you're up at night with a cough or congestion, a nap the next day can make up some of the lost sleep. The best time to take a nap is usually early afternoon.
Is it bad to sleep all day when sick?
No, sleeping most of the day during the first few days of an illness like the flu is common and usually fine. Your body is putting its energy into fighting the infection. What matters is the trend: you should be gradually needing less sleep as you recover.
If you're sleeping all day and it isn't getting better, or you're not sure why you're so tired, read is it bad to sleep all day for the common causes and when to check in with a doctor.
How to sleep better when you're sick
- Raise your head with an extra pillow if congestion or a cough keeps you awake.
- Keep fluids nearby, and sip through the day so you're not waking up parched.
- Check your medicine labels. Some daytime cold products contain decongestants, and some pain relievers contain caffeine, both of which can keep you up, while "nighttime" versions often contain drowsy antihistamines.
- Keep the room cool and dark, and lower your screen brightness.
- Skip alcohol. It can make sleep lighter and more broken.
- Take time off if you can. Rest is easier at home, and you won't pass the illness to coworkers.
When to see a doctor
Most colds and mild flu get better on their own with rest. See a doctor or seek urgent care if you have:
- Trouble breathing, shortness of breath or chest pain
- Confusion, or you're very hard to wake up
- A high fever that won't come down, or lasts more than a few days
- Signs of dehydration, like very little urination or dizziness when you stand
- Symptoms that improve and then come back worse
- Symptoms that drag on for more than a week or so without improving
- A long-term condition, like asthma, diabetes or heart disease, that is getting worse
Babies, older adults, pregnant people and anyone with a weakened immune system should call a doctor sooner.
Once you're better, check whether you're carrying extra sleep debt from the rough nights, and get back to a regular bedtime with the sleep calculator.