Fever dreams: what they are, what they mean, and causes

Clinically reviewed by Dr. Chris Mosunic, PhD, RD, CDCES, MBA

Fever dreams and fever hallucinations can feel intense. Learn what causes them, the effects of high fever on the brain, and tips to prevent weird fever dreams.

Fever dreams are a common experience when our body temperature rises due to illness. They can be vivid, often bizarre in nature, and cause us to wake up confused. 

Fever dreams might feel more intense and strange than our usual dreams. If you experience fever dreams, understanding their potential meanings and causes, and how to prevent them can help you manage this unsettling aspect of being sick.

 

What are fever dreams and fever hallucinations?

When your body is fighting off an illness and your body temperature is higher than normal, it can change the way your brain works, leading to what we call fever dreams. Fever dreams are different from the regular type of dream you have—they’re more intense and often feel very real, with everything in the dream seeming clearer.

Fever hallucinations are slightly different. They happen when your fever is very high and can happen even when you're awake. You might see or hear things that aren't there, which can be startling or confusing.

Both fever dreams and hallucinations are your brain's way of reacting to the unusual conditions created by the fever, like the higher temperature, the fight against illness, and your body's overall discomfort. All of these can influence what you dream about or what you think you see and hear.

Knowing that fever dreams and hallucinations are just part of how our body and brain react to illness can make them less scary. They're a temporary side effect of your body doing its job to heal.

 

The difference between fever dreams and normal dreams

Fever dreams can be quite different from the dreams you might have on a regular night. While they can be unsettling, remembering that they're a temporary and natural response to illness can provide some reassurance. Here are some of the ways to differentiate between the dreams and hallucinations. 

  • More intense emotions: Fever dreams often come with stronger emotions. You might feel fear, sadness, or confusion more deeply in these dreams.

  • Troubling content: Many people find that their fever dreams are troubling or disturbing. They might involve unusual or unsettling scenarios that don't usually show up in normal dreams.

  • Strangeness: In fever dreams, you might dream about peculiar things that don't make sense, or have a strange mix of people and places that don't usually go together.

  • Scarier experiences: Fever dreams are often more frightening than your average dream, and might cause anxiety or fear.

Distorted perception of space and time: In fever dreams, how you perceive space and time can be skewed. You might find that things seem bigger or smaller than they are, or time might seem to speed up or slow down.

 

How fever affects your sleep 

Surprisingly, a fever can actually change how your body and brain work, and this can have a big impact on your sleep.

When your body's temperature rises higher than the normal range of 98.6°F (37°C) to fight off infections, this increase can make your body feel and act differently.

Fevers can have several common symptoms that can make it hard to get a good night's sleep. If you're having trouble managing your fever symptoms or they're getting in the way of your sleep, check-in with a healthcare professional. Some symptoms of fever to look out for include:

  1. Feelings of weakness

  2. Warmth and sweating

  3. Headaches

  4. Shivers and chills

What causes fever dreams and hallucinations?

The main cause of fever dreams is the high temperature itself. When you have a fever, your body temperature rises. When your brain's normal temperature is altered because of a fever, it can start to work a bit differently, which can lead to more intense, strange, or scary dreams and hallucinations.

Even though scientists have studied fever dreams, there's still no exact explanation for why they happen. Some experts think that the high temperatures might disrupt the normal processes of the brain. However, not everyone who has a fever will experience fever dreams or hallucinations.

Fever dreams and hallucinations are a part of how our body and brain react to illness and high temperatures. They’re usually temporary and go away once the fever subsides. If you're concerned about your fever dreams or hallucinations, especially if they're very disturbing or if your fever is very high, it's a good idea to talk to a doctor or healthcare professional. If you have a fever with an illness, consult your doctor about taking fever-reducing medication to help keep your body safe.

 

6 ways to prevent fever dreams

When you're dealing with a fever, vivid and often unsettling fever dreams can occur. But there are ways to reduce the chances of having these intense dreams. These tips are to help you feel more comfortable and possibly prevent fever dreams, but if your fever is high or you're feeling really unwell, it's best to see a doctor.

1. Get plenty of rest

When you're sick, your body needs more rest than usual. Getting enough sleep gives your body the time it needs to fight off the illness. Try to create a comfortable, restful sleep environment. This means sleeping in a quiet, dark room and on a comfortable bed.

💙 If you’re feeling under the weather, it can be comforting to have a gentle night time routine that includes relaxing activities. Press play on our Soften Into Sleep meditation. 

2. Stay hydrated

When you have a fever, it’s important to drink a lot of fluids like water and drinks with electrolytes (without added sugar). The extra hydration helps your body cool down and fight off illness. Try water, fresh fruit juices or herbal teas, but remember to avoid caffeine as it can make it harder to sleep.

3. Eat light and easy-to-digest foods

If your physician has cleared you to eat them, try to eat a little, even if you don’t feel like it. Stick to foods that are easy on your stomach, like toast, rice, or bananas. These won't overwork your digestive system and can help keep your energy up.

4. Take lukewarm baths

A cool bath can help bring down your body temperature. But make sure the water is lukewarm, not cold—cold water can shock your system, which isn't good when you're already feeling unwell.

💙 Try one of our soothing soundscapes like City Rain to add a bit more relaxation to your bath. 

5. Manage room temperature

Keep your room at a comfortable temperature—not too hot and not too cold. Sometimes, a slightly cooler room can help you sleep better when you have a fever.

💙 Try Green Noise (with River) to block out unwanted disruptions and make your sleep space more peaceful. 

6. Try over-the-counter fever reducers

Medications like acetaminophen (Tylenol) or ibuprofen (Advil or Motrin) can be effective in reducing fever. By lowering your body temperature, these medications may help reduce the intensity of fever dreams. However, it's important to use them as directed and consult with a healthcare provider, especially if the fever is persistent or if you have other health conditions.

 

Fever dreams FAQs 

Why are fever dreams so weird?

Fever dreams feel weird because they're much more intense than your regular dreams, and sometimes they don’t make much sense. When you have a fever, the higher temperature can make your brain work differently. This can make dreams feel more vivid, emotional, and sometimes even scary or confusing. This is why fever dreams can feel so strange and memorable.

What do fever dreams mean?

Fever dreams don't have a specific meaning. Unlike some dreams that might reflect your thoughts or feelings, fever dreams are your brain reacting to the fever. The high temperature can make your brain create weird and vivid dreams. It's not really about the dream meaning something about your life, just your body responding to being sick.

Can you prevent fever dreams?

Preventing fever dreams entirely might not be possible, but make sure you're resting enough, staying hydrated, and keeping your body as cool as possible to reduce the likelihood of having intense dreams. Creating a comfortable sleeping environment can also make a difference as you make it easier for your body to deal with the fever.

How do fever dreams differ from nightmares?

Fever dreams and nightmares can both be scary, but they happen for different reasons. Nightmares are scary dreams that can happen anytime, fever or no fever. Fever dreams happen specifically when you have a high body temperature. They're often more intense and bizarre than regular dreams or nightmares because of how the fever affects your brain.

Can fever dreams be a sign of a serious health issue?

Fever dreams themselves are usually just a symptom of having a fever and aren't typically a sign of a more serious health issue. However, if you have frequent fever dreams along with a high fever, or if they're very disturbing, it's a good idea to see a doctor. This is especially true if your fever is very high or lasts for a long time.


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