Fever Dreams: Symptoms, Causes, and Prevention - Healthline

If you've ever had a particularly intense dream while you're sick, it may have been a fever dream.

A fever dream is a term used to describe vivid dreams you have when your body temperature is elevated.

For many people, these dreams can be disturbing and unpleasant.

A dream is essentially a series of thoughts, images, and sensations you have while sleeping. Scientists believe you have your strongest dreams during the rapid eye movement (REM) stage of sleep.

Though researchers don't know exactly why you dream, certain factors such as daily activities, foods, and health conditions might influence your sleep visions.

When do they occur?

A fever dream occurs when your body temperature is higher than usual.

A normal body temperature ranges, usually between 97 and 99°F. Anything higher than 2 degrees above your normal temperature is considered a fever.

You might develop a fever because your body is responding to:

• a viral or bacterial infection
• heat exhaustion
• certain inflammatory conditions such as rheumatoid arthritis
• medicines, such as antibiotics
• an immunization
• a tumor

What are fever dreams like?

Most people describe fever dreams as a distressing experience. In fact, in one 2016 study, about 94 percent of participants described their fever dreams as negative.

Though a fever dream is known in medical literature, scientific studies on the phenomenon are limited.

In a small 2013 study, scientists surveyed participants' fever symptoms. Results showed 11 percent of them reported fever dreams.

People often describe a fever dream as emotionally intense, troubling, strange, or scary. These dreams may also include less social interaction scenarios than normal dreams.

In the 2013 study, one volunteer said their dreams would move "back and forth between a very difficult circumstance and a very comfortable circumstance."

A recent online study looked at 164 individuals, 100 of whom reported a recent fever dream. The authors found that fever dreams were more bizarre, negatively toned, and included more references to health and temperature perception compared to normal dreams.

Scientists don't know exactly why fever dreams occur, but there are some theories.

One is that high temperatures might disrupt the brain's normal cognitive processes.

Authors of the 2020 study wrote, "The basic idea is that the 'over-heated' brain is not functioning properly and, therefore, dreams are more bizarre."

During the REM stage of sleep, where most of your vivid dreams occur, your body tends to have a harder time controlling your internal temperature. A fever may add to this already strained process, which can lead to the unpleasant dreams.

Fevers might also trigger waking hallucinations (seeing things that aren't really there), irritability, and confusion.

There might not be a foolproof way to prevent fever dreams altogether but controlling your body temperature could be helpful.

If you have a fever, be sure to:

• get plenty of rest
• drink lots of fluids
• take a fever-reducing medicine, such as ibuprofen (Advil), acetaminophen (Tylenol), or aspirin
• eat foods that are easy to digest
• bathe in lukewarm water

Fever dreams share some of the same symptoms as lucid dreams, which are dreams that happen when you're aware that you're dreaming.

People who have both fever dreams and lucid dreams are able to recall the details of their dreams. Both types also occur in the REM stage of sleep.

But, lucid dreams aren't linked to higher body temperature, and they aren't always unpleasant or negative in nature like fever dreams.

Additionally, lucid dreams are sometimes controllable, meaning you can train yourself to have one.

Fever dreams are a mysterious occurrence that happen when your body temperature rises. They're usually described as a disturbing and stressful experience.

While there's no guarantee you can completely prevent a fever dream, treating your fever may help control these vivid nightmares.