Sleep Deprivation Stages (and How To Avoid Them)

July 8, 2021 | Casper Editorial Team

Disclaimer: This article is for informational purposes only and should not be taken as medical advice.

We’ve all had those nights of little to no sleep. Whether it’s because we’re up late finalizing travel plans, suffering from sleep anxiety, or stuck listening to a snoring partner, the effects of not getting enough sleep — a term often referred to as “sleep deprivation” — can be all too apparent the next day. 

Understanding sleep deprivation stages and their associated symptoms can help you recognize when you’re getting an insufficient amount of sleep. Typically, the longer you keep yourself from sleeping, the worse your symptoms become. Keep reading to learn more about sleep deprivation stages and what you can do to make sure you’re giving your body the sleep it needs. 

What Is Sleep Deprivation?

Sleep deprivation is what happens when you don’t get the full amount of sleep your body needs to function properly. You’re likely to feel fatigued, less able to focus, and your reaction time may be slowed.

There are myriad sleep deprivation causes, some of the most prevalent being socializing, relaxing, and engaging in other leisure activities. Some of us also inadvertently practice revenge bedtime procrastination to steal back a few hours of our day, leading to a lack of sleep. 

Sleep Deprivation Symptoms

Not getting enough sleep can cause a variety of side effects, but the main ones are daytime drowsiness and impaired cognitive functions. Lack of sleep can affect your whole day, as your ability to concentrate may be lessened and you’re likely to suffer from insufficient energy. It’s also one of the main reasons why we yawn during the day. Other possible symptoms of sleep deprivation can include: 

  • Irritability/anger 
  • Drowsiness
  • Impaired concentration
  • Increased stress 
  • Food cravings 
  • Slowed reaction time
  • Visual misperceptions 
  • Hallucinations 

Stages of Sleep Deprivation by Hour

The early stages of sleep deprivation don’t affect everyone the exact same way. You may have worse side effects than someone else even after staying awake for the same amount of time. For this reason, you should be aware of different potential symptoms associated with each stage. 

If you’re experiencing severe symptoms from lack of sleep, it’s best to consult a medical professional. It’s particularly important to see a doctor if you’re experiencing any kind of sleep problem that’s preventing you from getting the sleep your body needs. 

Stage 1: 24 Hours of No Sleep

Staying up for 24 hours is unlikely to cause any severe symptoms, but you’ll likely feel tired and experience some side effects. 

Keep in mind that while the symptoms may be manageable, any form of sleep deprivation can make everyday tasks difficult to do. Driving and other activities that require full attention can even prove dangerous. In fact, lack of sleep for 24 hours or more is equivalent to having a blood alcohol level of 0.1% — higher than most states’ legal limit. 

While everyone experiences different sleep deprivation symptoms, some common ones you may feel at this stage are:

  • Irritability/anger 
  • Drowsiness
  • Impaired concentration
  • Increased stress 
  • Food cravings 
  • Slowed reaction time

Stage 2: 36 Hours of No Sleep

Your symptoms will gradually get worse after going 36 hours without sleep. Aside from drowsiness and impaired concentration, your physical health may begin to take a toll. One study suggests that you’re likely to have an increased appetite and a higher risk of developing cardiovascular disease over an extended period of time. 

Stage 3: 48 Hours of No Sleep

On top of all the previous side effects mentioned, after going two days without sleep, you may also experience short periods of unintentional “microsleep.” When this happens, you doze off for a few seconds and your brain is in a state similar to when you’re sleeping. 

Along with microsleeps, you may also experience other sleep deprivation symptoms, such as: 

  • Immune system decline 
  • Increased confusion 
  • Depersonalization 
  • Increased irritability

Stage 4: 72 Hours of No Sleep

After going 72 hours (or three days) without sleep, the previous symptoms listed above can become more severe. Not only can you experience worsened mood and higher cholesterol levels, but your urge to sleep will likely be extremely intense. At this stage, you may also experience disordered thinking and hallucinations.  

Stage 5: 96+ Hours of No Sleep

Going 96 hours or more without sleep can be very dangerous for your body. Sleep is your body’s way of recharging. Studies have shown that the longer time we spend without sleep, the more psychotic systems we begin to develop. This can range from simple visual misperceptions to complete sleep deprivation hallucinations. After going 96 hours with no sleep, your perception of reality is likely to be distorted. 

How To Prevent and Treat Sleep Deprivation

Many people suffer from the inability to fall asleep right away or unintentionally waking up at various times throughout the night. While some conditions should be discussed with a medical professional, there are a few things you can do to help set yourself up for a successful night of sleep. Likewise, there are also some things you can do to help with the lack of sleep you might be experiencing. 

Take a Power Nap

Taking a power nap the right way can help ease drowsiness and increase your focus. Just be sure to nap four to five hours before bedtime to make sure you’ll still be able to fall asleep later as well.

Sleep a Few Extra Hours Each Night 

Sleeping a few extra hours each night or just every once in a while can help your body get the full amount of sleep it needs. However, be cautious about oversleeping, as this has some negative side effects as well.

Go To Bed a Bit Earlier 

By intentionally planning out when you’ll go to sleep, you’ll be able to create a routine for your body that can make falling asleep a bit easier. Starting your sleep schedule a little earlier so you can go to bed sooner can help combat feelings of sleep deprivation. 

Practice Sleep Hygiene 

Practicing good sleep hygiene has the potential to improve your ability to both fall asleep and stay asleep. Good sleep hygiene includes exercising regularly, avoiding stimulants a few hours before bed, and putting technology away at least an hour before bed.   

Improve Your Bedroom Environment 

Not all sleepers are made equal. However, there are a few general recommendations that anyone can apply to create a sleep-inducing bedroom environment. By setting your bedroom to a certain temperature and using colors that elicit sleep, you’ll be more eager to go to bed and better able to fall asleep. If you need to get some shut-eye on the road, you can also adapt your space to sleep in a car all night long.

Avoid Caffeine at Night

It’s best to avoid drinking caffeine such as coffee or soft drinks at least four or five hours before you plan to go to sleep. If you’re craving something to eat or drink, munch on  some nuts or another healthy nighttime snack.

Talk to Your Doctor

If you’re having trouble falling or staying asleep consistently, you may have an underlying condition and should seek the advice of your doctor. They can help identify the problem and give you different treatment options as necessary. 

While the sleep deprivation stages carry their own side effects, each should be taken seriously. Not getting a sufficient amount of sleep for your body can cause drowsiness, impaired focus, and, in extreme cases, hallucinations.

There are many causes of sleep deprivation, from serious medical conditions to lousy mattresses that make it impossible to sleep. If your sleeping arrangements are comfortable, it’s best to see a doctor. But if you’re sleeping on a mattress or pillow that causes discomfort and wakes you regularly, it may be time to find a new mattress or pillow better suited for your needs.