Can sleep deprivation cause hallucinations? Plus, how to prevent it
Clinically reviewed by Dr. Chris Mosunic, PhD, RD, MBA
Learn how sleep deprivation can lead to hallucinations and strategies to prevent them. Plus, explore the connection between mental health and sleep loss.
Nothing feels better than a good night’s sleep, but some evenings no matter how hard you try, you just can’t find slumber. We’ve all been there — tossing and turning, unable to sleep, only to wake up the next morning feeling drained. You might feel tired, cranky, or struggle to focus, but once you get a good night’s sleep the next night, things go back to normal. But what happens when you don’t sleep for much longer than that?
When sleep deprivation drags on for days, it can lead to some alarming effects. One of the most surprising and unsettling outcomes of severe sleep deprivation is hallucinations. (Yes, really!)
Here’s what to know—and do—if you’re currently suffering from them.
What are sleep deprivation hallucinations?
Sleep deprivation hallucinations can happen when you get so overtired that your brain starts to misfire, causing you to see or hear things that aren’t really there. These experiences can feel real—even though they aren’t—because your brain’s struggling to function properly.
You might see flashes of light, shadows, or faces that don’t actually exist. You might even hear voices or strange sounds. Less commonly, you might feel sensations like bugs crawling on your skin.
Hallucinations from lack of sleep usually happen after 24 hours or more of sleep deprivation, but they can get worse the longer you go without sleep. In some cases, it may even feel like you’re dreaming while you’re awake. (And if you’re reading this right now after a bad night of sleep, here’s what to do.)
What science says about hallucinations caused by sleep deprivation
When you’re sleep-deprived, your brain has trouble processing information and keeping you alert. The longer you go without sleep, the more your brain struggles — especially in areas responsible for how you perceive things. As a result, you can hallucinate. And while hallucinations are temporary and typically go away once you get enough sleep, they can worsen depending on how long you stay awake.
After 24 hours: Mild hallucinations can start. You might see things like flashes of light or shadows that aren’t really there. Your brain’s already tired and struggling to interpret what’s real.
After 48–72 hours: More intense hallucinations may happen, including seeing detailed images, hearing sounds that don’t exist, or feeling things like bugs crawling on your skin. At this point, your brain’s so exhausted it’s blurring the line between wakefulness and dreaming.
Microsleeps: As you get more tired, parts of your brain may shut down for a few seconds, going into a dream-like state while you’re still awake. This can bring confusing and sometimes frightening hallucinations.
Severe cases (psychosis): Staying awake for several days can cause sleep deprivation psychosis, where you lose touch with reality, and experience delusions or more extreme hallucinations.
8 symptoms of sleep deprivation (besides hallucinations)
While hallucinations are one of the more dramatic symptoms of sleep deprivation, your body has lots of ways of telling you that it’s time to slow down and prioritize sleep. While it might feel like you can “power through” a few sleepless nights, the effects can build up quickly, making it harder to function.
Memory problems: You may forget simple tasks or lose your train of thought more frequently than usual.
Difficulty concentrating: Difficulty staying focused on everyday activities like reading, working, or holding a conversation can become tough. (If concentrating has been tough lately, these eight strategies can help.)
Irritability and mood swings: Small things annoy you more than usual, and you feel more emotional or frustrated.
Physical exhaustion: You might experience slower reflexes, poor coordination, or feel physically weak.
Slowed reaction time: Impaired performance—similar to alcohol intoxication—can go unnoticed until a quick response is needed, like when you’re driving or operating machinery.
Weakened immune system: You may get sick more often or take longer to recover from illnesses.
Poor decision-making and judgment: You might have a tough time evaluating situations, such as at work or in relationships, or make impulsive decisions.
Increased anxiety and stress: Minor challenges feel overwhelming, with ongoing stress impacting both mental and physical health. (Feeling anxious now? Use these 20 affirmations to get some relief.)
The link between sleep deprivation and mental health
Sleep is closely linked to our mental health. Studies have shown that when you’re not getting enough sleep, you’re more likely to experience symptoms of anxiety and depression. And if you’ve been diagnosed with bipolar disorder, sleep deprivation can worsen symptoms. And when sleep deprivation becomes chronic, it can become harder to manage emotions and stress.
Sleep deprivation may also cause or intensify psychotic symptoms. People with conditions like schizophrenia are especially vulnerable, but someone without a history of mental illness can also experience psychosis if they go without sleep for long enough.
How to prevent hallucinations caused by sleep deprivation
Hallucinations caused by sleep deprivation can be scary — but there are steps you can take to ward them off. Here are a few simple strategies to help you get the rest you need.
1. Stick to a regular sleep schedule
Go to bed and wake up at the same time every day (even on weekends). Maintaining consistency is one of the most important things you can do to improve your sleep and help regulate your body’s internal clock. When you’re in a routine, your body naturally starts to feel sleepy at the right time, and you wake up feeling more refreshed. Check out these extra 10 tips to help you get better sleep at night.
2. Create a calming bedtime routine
About 30–60 minutes before bed, start winding down by reading a book, stretching, journaling, or listening to soft music. Avoid anything that gets your mind racing, like watching intense TV shows or scrolling through social media. By doing the same calming activities each night, you help your brain associate these actions with bedtime, making it easier to fall asleep. Here are nine tips to help you create your ideal bedtime routine.
💙 Try listening to Wonder, a Sleep Story narrated by Matthew McConaughey, designed to guide you into deep sleep.
3. Limit screen time before bed
Yes, it’s true — screen time really does affect your sleep. Blue light from phones, tablets, and computers can trick your brain into thinking it’s still daytime, which makes it harder to fall asleep.
Put your devices away at least an hour before bed, and if you need to use your phone or computer late at night, try a blue light filter or “night mode” to lessen the impact.
4. Be mindful of what you eat and drink
Caffeine—a stimulant found in coffee, tea, and soda—can stay in your system for hours and keep you awake. Avoid these drinks too close to bedtime, but also watch how much you drink in general, to avoid waking up for bathroom trips during the night.
Having big meals late at night can also make it harder to fall asleep, as your body’s busy digesting. If you’re hungry before bed, go for a light snack—like a banana or a handful of nuts—as they’re less likely to be disruptive.
5. Create a comfortable sleep environment
Make your bedroom feel calm and relaxed with soft bedding, a supportive pillow, and the right room temperature — preferably between 60–67°F (15–19°C). If outside sounds are a problem, try a white noise machine or earplugs. And if light sneaks in through your windows, use blackout curtains or a sleep mask to help create a dark, peaceful space. Here are eight more tips to help you create an ideal sleep environment.
6. Manage stress and anxiety
If you’re unable to fall asleep because your mind is racing, try relaxation techniques before bed. Use deep breathing exercises, progressive muscle relaxation, or meditation to help calm your mind. Write your thoughts in a journal to get them out of your head and onto paper. And manage stress during the day by staying organized, setting realistic goals, and making time to do things you love.
7. Exercise regularly
Regular exercise can help you fall asleep faster and more deeply because you feel more tired by bedtime. Fit in some movement each day, like a walk, jog, yoga session, or sports training session, but be sure to finish your workout a few hours before bedtime so you’ve got plenty of time to wind down.
💙 Try gentle movement in your Evening Wind Down Routine with guidance from Mel Mah on The Daily Move.
8. Take naps if needed, but keep them short
If you’re really struggling with sleep deprivation, take a nap to help recharge your brain and give you a much-needed energy boost. But, be careful not to nap too late in the day or for too long, as this can make it harder to fall asleep at night.
Get your snooze in the early afternoon, when you might experience a natural dip in energy, and keep it to 20–30 minutes to help you avoid disrupting your sleep schedule. Here’s how to power nap like a pro.
What to do if hallucinations have already started
If you’ve already started experiencing hallucinations due to sleep deprivation, prioritize sleep right away to protect your overall wellbeing. Even a short nap can help reduce the hallucinations and give your brain some much-needed rest.
Pay attention to your body’s warning signs too. If you’re regularly losing sleep and noticing serious effects like hallucinations, it’s a sign that your sleep habits need to change. Speak with your doctor to find out if an underlying issue—like insomnia or sleep apnea—is preventing you from getting the rest you need.
Sleep deprivation hallucinations FAQs
How long can a person go without sleep before hallucinations start?
Most people can go about 24 hours without sleep before they start experiencing noticeable effects, and hallucinations can start after that.
After staying awake for a full day, you might start seeing things out of the corner of your eye, like shadows or flashes of light. This is usually a sign that your brain’s getting tired and struggling to process information correctly. For some, more intense hallucinations—like seeing detailed images or hearing sounds that aren’t there—may start to happen after about 48 to 72 hours without sleep.
Everyone’s body reacts differently, so some people might experience these effects a little earlier or later. If you’re starting to hallucinate, it's clear you need to go to sleep immediately. While hallucinations caused by sleep deprivation typically aren’t permanent, they do indicate that your body is in distress and desperately needs rest to recover.
What other mental health conditions can be triggered by sleep deprivation?
Sleep deprivation can trigger or worsen conditions like anxiety, depression, and bipolar disorder. When you’re sleep-deprived, your brain struggles to regulate emotions, making it harder to cope with stress and anxiety. Small problems can start to feel overwhelming, and you may find yourself more anxious or irritable than usual. In fact, people who don’t get enough sleep are much more likely to develop anxiety symptoms or feel more stressed than they would with adequate rest.
Depression is also closely linked to sleep deprivation. Chronic lack of sleep can lead to feelings of sadness, hopelessness, and disconnection from the people around you. If you already suffer from depression, sleep deprivation can make it feel even harder to manage your symptoms (but these 12 tips can help you cope).
For people with bipolar disorder, poor sleep can trigger manic episodes—where you feel overly energized or impulsive—or deepen depressive episodes, making it harder to function day-to-day. Because sleep and mental health are so closely connected, addressing sleep issues can often help improve your emotional wellbeing and help you feel more balanced.
Can hallucinations from sleep deprivation be permanent?
Hallucinations caused by sleep deprivation are typically a temporary response to extreme exhaustion, and once you get the sleep your body and brain need, the hallucinations should disappear.
However, regularly experiencing sleep deprivation can have long-term effects on your mental and physical health. This means it’s important to address sleep issues before they become more serious.
How can you recover from prolonged sleep deprivation?
The best way to recover from prolonged sleep deprivation is to return to a healthy sleep routine. With time and consistency, your body will adjust, and you’ll start feeling more rested and alert again.
Start by getting a full night’s rest as soon as possible. Aim for 7–9 hours if you can. Your brain and body need time to recover, and it may take several nights of good sleep to feel fully back to normal.
Take a short nap (about 20–30 minutes) during the day if you’re really struggling with exhaustion. This can help recharge your brain without compromising your nighttime sleep.
Next, focus on building better sleep habits. Stick to a consistent bedtime and wake-up time, and create a relaxing bedtime routine to help you wind down.
Have good sleep hygiene. This means avoiding caffeine and heavy meals before bed, and limiting screen time.
Manage your stress during the day, as anxiety can make it harder to sleep (here are seven tips to help).
If sleep deprivation continues to be a problem, speak with a healthcare provider or sleep specialist to address any underlying issues—like insomnia or sleep apnea—that may be affecting you.
Are certain people more prone to sleep deprivation hallucinations than others?
In general, the more sleep-deprived you are, the higher your chances of experiencing hallucinations, regardless of your risk factors. Still, some people are more prone to sleep deprivation hallucinations than others.
Mental health conditions: People who already struggle with mental health conditions, like anxiety, depression, or schizophrenia, may be more sensitive to the effects of sleep deprivation and more likely to experience hallucinations when they’re running low on rest.
Stress: Anyone dealing with high levels of stress may find it harder to sleep and, in turn, are more likely to experience sleep-related symptoms like hallucinations.
Genetic makeup: Some people naturally need more sleep than others, and when they don’t get it, they might be more likely to experience hallucinations or other cognitive disruptions.
Age: Adolescents and young adults may be more resilient to short-term sleep deprivation, but older adults might experience the effects more quickly.
Disrupted sleep schedules: Shift workers or people who frequently disrupt their sleep schedules are at higher risk because their bodies may be out of sync with their natural sleep rhythms.
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