Fever Dreams

What Is a Fever Dream?

Fever dreams are vivid, often unpleasant dreams sleepers can experience when they have a fever. In multiple studies, sleepers describe their fever dreams as bizarre, negative, and emotionally intense Trusted Source American Psychological Association (APA)APA is the leading scientific and professional organization representing psychology in the United States, with more than 121,000 researchers, educators, clinicians, consultants and students as its members.View Source . Experiences of fever dreams vary among sleepers. Some people with fevers don’t recall dreaming, while others can recall their fever dreams Trusted Source National Library of Medicine, Biotech InformationThe National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.View Source years later.

While fever dreams can occur during any stage of sleep, most vivid dreams happen during rapid eye movement (REM) sleep Trusted Source National Institute of Neurological Disorders and Stroke (NINDS)NINDS aims to seek fundamental knowledge about the brain and nervous system and to use that knowledge to reduce the burden of neurological disease.View Source . 

Specific aspects of fever dreams can include:

• Spatial distortion: Moving walls, objects melting, and spaces changing size were the most common type of dream in one study of fever dreams.
• Threats or danger: Study participants reported that their fever dreams contained threats from dogs, insects, terrorists, and stones.
• Illness: Types of illness in dreams may vary. In one study, sleepers dreamed about illnesses such as respiratory distress, pain, and vertigo.

Fever Dreams vs. Nightmares

While fever dreams are the result of a fever, nightmares may stem from anxiety Trusted Source Medline PlusMedlinePlus is an online health information resource for patients and their families and friends.View Source , stress, or trauma. These frightening and unsettling dreams could also be indicative of a sleep disorder, such as sleep apnea or narcolepsy. Regardless of cause, nightmares can impact sleep quality.

Reducing stress and practicing good sleep hygiene can help decrease the likelihood of nightmares. More severe cases may require cognitive behavioral therapy. Additionally, a sleep study can determine if a sleep disorder is present.

Fever Dreams vs. Lucid Dreams

During lucid dreams, the dreamer becomes aware they’re asleep Trusted Source National Library of Medicine, Biotech InformationThe National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.View Source . Some lucid dreamers even experience control over their dreams. In one study of fever dreams, nearly 40% were described as lucid. This number is significantly higher than the 7.5% of dreams experienced as lucid dreams in healthy people.

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What Causes Fever Dreams?

To understand what might cause fever dreams, it helps to first understand the fevers that cause them. 

A fever is a sign of inflammation, and one of the body’s potential responses to infection or illness Trusted Source Medline PlusMedlinePlus is an online health information resource for patients and their families and friends.View Source . Although there’s wide variability of body temperature among individuals, a standard human body temperature is generally considered about 98.6 degrees Fahrenheit (37 degrees Celsius). Fevers are an elevated body temperature Trusted Source Merck ManualFirst published in 1899 as a small reference book for physicians and pharmacists, the Manual grew in size and scope to become one of the most widely used comprehensive medical resources for professionals and consumers.View Source of 100.4 degrees Fahrenheit (38 degrees Celsius) or greater, taken orally in adults.

Symptoms of fever may include:

• Cold or chills Trusted Source National Library of Medicine, Biotech InformationThe National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.View Source
• Rigors, or severe, teeth-chattering and shaking chills Trusted Source Merck ManualFirst published in 1899 as a small reference book for physicians and pharmacists, the Manual grew in size and scope to become one of the most widely used comprehensive medical resources for professionals and consumers.View Source
• Weakness
• Warmth
• Dampness or sweating
• Headache
• Respiratory symptoms such as cough, shortness of breath, or difficulty breathing
• Fever dreams or hallucinations

There are no studies that explain exactly how fevers cause fever dreams, but researchers have developed theories. Some speculate that the “overheated” brain Trusted Source National Library of Medicine, Biotech InformationThe National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.View Source affects cognitive processing and therefore makes the fever dreams more strange than typical dreams. 

Other researchers have noted that fever dreams seem to support the continuity hypothesis of dreaming, which proposes that our waking life and dreams are directly connected Trusted Source Consciousness and CognitionView Source . It follows that dreams during a negative, abnormal experience like sickness would produce stranger and more negative dreams. 

Fevers can also interrupt REM sleep, which may lead to other sleep changes, including unusual dreams.

Do Fever Dreams Have a Meaning?

As is the case with normal dreams, the meaning of fever dreams is still up for debate. As noted, researchers generally agree that all types of dreams tend to reflect waking life to some extent. In fact, one study of 299 dreams showed that half of the dreams Trusted Source National Library of Medicine, Biotech InformationThe National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.View Source contained at least one component tied to a specific daytime experience.

In the case of fever dreams, a recent survey found that many of those who experienced fever dreams reported that the dreams included more references to health and temperature perception than usual.

However, there’s no scientifically accepted meaning of fever dreams, or even regular dreams. Dream interpretation theories are varied and still debated. For example, the psychoanalysis of Sigmund Freud and Carl Jung suggests a connection between dreams and the subconscious Trusted Source National Library of Medicine, Biotech InformationThe National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.View Source Trusted Source Behavioral SciencesView Source .

Modern theories propose that they may help with memory consolidation Trusted Source Current Neurology and Neuroscience ReportsView Source or with processing difficult emotional experiences Trusted Source Frontiers in PsychologyView Source . Scientists haven’t yet confirmed any of these theories with empirical evidence, because the nature of dreaming is so subjective Trusted Source Frontiers in PsychologyView Source . 

That said, the study of dreams is ongoing, and advances in neuroscience may one day allow researchers to gain a more complete understanding of the nature of dreams.

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When to Talk to a Doctor

While fever dreams themselves don’t require a visit to the doctor, you should monitor your fever and its other symptoms closely and seek professional help if you experience any of the following: Trusted Source Medline PlusMedlinePlus is an online health information resource for patients and their families and friends.View Source

• A fever after traveling to a different country 
• A fever of 105°F (40.6°C) or higher that doesn’t come down quickly with treatment
• A fever that remains at or keeps rising above 103 degrees Fahrenheit (39.4 degrees Celcius)
• A fever for longer than 48 to 72 hours
• Fevers that come and go for a week or more, even if they aren’t high
• A fever in conjunction with a serious medical illness, such as heart problems, sickle cell anemia, diabetes, cystic fibrosis, COPD, or other chronic lung problems. 
• A fever that occurs along with a new rash or series of bruises
• A fever that occurs with pain urinating
• A fever that occurs with a weakened immune system (from chronic steroid or immune suppressing therapy, a bone marrow or organ transplant, spleen removal, HIV/AIDS, or cancer treatment).
• A fever after traveling to a different country

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