How Long Can You Go Without Sleep?

Medically Reviewed By Nick Villalobos, MD

Sleep is essential to good health. How long a person can go without sleep without serious effects may vary between individuals. However, getting regular and adequate sleep is the best way to promote good health and prevent long-term issues. Similar to food and water, sleep is a biological need and plays a vital role in brain function, physical performance, and long-term health. Without enough quality sleep, you can experience severe symptoms in as little as 36 hours, as well as long-term health consequences.

This article explains sleep deprivation and its short- and long-term effects on your health. It also covers how long you can go without sleep before experiencing severe symptoms.

Sleep deprivation

A person lying under pillows and cushions on their couch
EASY 2 SHOOT/Stocksy United

Sleep deprivation is a condition that occurs when you don’t get enough sleep or don’t sleep at all. This may be due to:

  • sleep disruption due to life circumstances, such as working a night shift when you are used to working during the day
  • not sleeping well or not getting the quality of sleep your body needs
  • a sleep disorder that impacts your sleep

More than 1 in 3 adults in the National Sleep Foundation’s (NSF) 2020 Sleep in America Poll say they aren’t getting enough quality sleep. They also report feeling sleepy during the day 3 times a week on average.

Read 7 sleep tips for people who work at night.

Effects of inadequate sleep after 24 hours

If you’ve ever pulled an all-nighter or had a rough night with no sleep, you probably know what it’s like to have excessive daytime sleepiness. But even one night of little or no sleep can also impact your mood and function.

According to the Centers for Disease Control and Prevention (CDC) Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source , impaired performance after being awake for 24 hours is similar to having a blood alcohol concentration (BAC) of 0.10%. For comparison, the United States considers people who drive with a BAC of 0.08% to be drunk driving.

Other short-term effects of sleep loss may include:

  • depressed mood
  • greater level of stress hormones, or increased stress
  • poor memory
  • reduced attention or concentration
  • reduced productivity
  • impaired coordination

Effects of inadequate sleep after 36 hours

After 36 hours of little or no sleep, you may have similar effects as 24-hour sleep deprivation, but they may be more intense or severe. You may also have more cognitive problems, including:

  • memory deficits
  • impaired decision-making
  • slowed reaction time
  • behavioral issues

Some people may also experience microsleep, which is when you doze off for brief periods without realizing it.

This is when lack of sleep begins to impact your physical health as well. A small 2018 study Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source involving people undergoing survival training made a few findings:

  • The 36-hour training period, when combined with sleep deprivation, impaired the body’s ability to protect itself against cell damage.
  • The training also induced muscle damage.

Effects of inadequate sleep after 48 hours

Once you go 48 hours without sleep, you may find it extremely hard to stay awake. You may feel disoriented or even experience hallucinations.

You may also experience:

Effects of inadequate sleep after 72 hours

After 72 hours, lack of sleep can heighten physical and cognitive impairments. A small 2015 study of astronauts found that, compared with people who were not sleep-deprived, those who were deprived of sleep for 72 hours had:

  • increased heart rates
  • increased negative mood
  • reduced positive emotions

Other potential effects include:

  • more frequent or longer microsleeps
  • illusions or delusions
  • paranoia
  • depersonalization, which means your thoughts and feelings might feel like they belong to someone else or aren’t real

Long-term effects of inadequate sleep on health

Sleep deprivation can have significant long-term effects, increasing your risk for new or worsened health problems. The CDC notes Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source that insufficient sleep has been linked to a number of chronic diseases and conditions, in particular:

A study from 2013 Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source showed that insufficient amounts of sleep were associated with an increased risk of death from cardiovascular and other diseases.

Sleep deprivation can also create Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source other sleep-related issues, such as:

Sleep requirements

The CDC provides general sleep guidelines Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source based on recommendations from the NSF, the American Academy of Sleep Medicine, and the Sleep Research Society. The guidelines are summarized in the table below.

Keep in mind that these are just guidelines. Everyone is different, and you may need an hour or two more or less to feel your best.

Age groupRecommended hours of sleep per 24 hours
newborns (0–3 months)14–17 hours (including naps)
infants (4–12 months)12–16 hours (including naps)
toddlers (1–2 years)11–14 hours (including naps)
preschoolers (3–5 years)10–13 hours (including naps)
school-age children (6–12 years)9–12 hours
teenagers (13–18 years)8–10 hours
adults (18–60 years)7 or more hours
older adults (61–65 years and older)7–9 or 7–8 hours

Learn 10 tips to help you sleep.


Nick Villalobos, M.D., has reviewed the answers to these common questions about sleep deprivation.

Can sleep deprivation be fatal?

Sleep deficiency can lead to a greater likelihood of death from cardiovascular and other diseases, as well as injuries due to impaired cognitive performance.

How long can you go without sleep before you die?

It’s not clear how long people can survive without sleep, but you may experience severe or extreme symptoms after just 36 hours of being sleep-deprived.

Should I go to the hospital if I haven’t slept in days?

If you haven’t slept in a few days, contact your doctor. They can evaluate your symptoms and help you determine if you need more immediate care.


Sleep deprivation can impact your physical and mental health and may be associated with cardiovascular and other diseases. After 36 hours of little to no sleep, you may experience severe symptoms, including memory deficits, depressed mood, and impaired decision-making. Some people experience episodes of microsleep, or falling asleep for brief periods during the day.

Long-term health effects of sleep deprivation include a number of chronic diseases and conditions. In extreme cases, death can occur.

If you have trouble sleeping or have gone days without sleep, talk with your doctor. It may take some trial and error, but there are things you can do to get the sleep you need.

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Medical Reviewer: Nick Villalobos, MD
Last Review Date: 2023 Feb 3
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