Can Stress Cause a Fever?

Stress can take a huge toll on your body. It may interrupt your sleep pattern, cause diarrhea, and even throw off your menstrual cycle. Because of its wide-ranging effects on your well-being, it's understandable to question whether stress can also cause another common sign of illness—a fever.

Fair warning: The research around stress and fevers—specifically the type of fever called "psychogenic fever"—was spotty, as of April 2022; but here, experts attempted to explain the connection between a higher body temperature and stress, and whether or not stressors could cause fever.

Can Stress Cause a Fever?

First, let's be clear on what a "fever" even is: According to the US National Library of Medicine's MedlinePlus resource, fever is a "body temperature that is higher than normal." MedlinePlus defined the "normal body temperature" for adults in the 97–99°F range, with the average at 98.6°F. The Centers for Disease Control and Prevention (CDC) defined fever more strictly: It's a body temperature of 100.4°F or greater.

While a fever is a sign of an infection or other illness, there wasn't, as of April 2022, a substantial body of research that proved an association between stress and a rise in body temperature. "Stress can cause some physiologic changes [like] blushing, turning red," Donald Ford, MD, a family medicine physician at Cleveland Clinic, told Health. "[But] that's very superficial. It doesn't alter the core body temperature."

Ramiro Jervis, MD, an internal medicine doctor at the Family Health Centers at NYU Langone, told Health that he was "not aware of any studies that [show] stress itself can cause fever." Dr. Jervis also said that, if a patient presents with a fever, their healthcare provider is likeliest to look for causes other than stress, such as an infection.

But while stress itself might not be able to directly cause fever, it can still do some serious damage to your body—and that can indirectly result in a fever. Specifically, enduring stress for a prolonged period of time can weaken or alter your body's immune system, Dr. Ford said.

Having lower levels of stress hormones may protect you against illnesses, per MedlinePlus. (FYI: This is why exercise can help build your immunity: When you work out, it slows the release of stress hormones in the body.)

Alka Gupta, MD, an assistant professor of medicine at Weill Cornell Medicine in New York, said that stress "can depress your immunity, making you more vulnerable to viral—or other—infections," which, in turn, could cause a fever.

What About Something Called 'Psychogenic Fever'?

When you look up, "Can stress cause a fever?" you're likely to read about something called a psychogenic fever, which is presumed to be just that: a fever as a result of stress. "Psychogenic" means rooted in a psychological origin, as opposed to a physical one. This type of fever is also called "neurogenic fever."

As of April 2022, little research was done on the topic of psychogenic fever, and it wasn't a widely accepted condition among healthcare providers.

A notable paper on psychogenic fever came out in 2015 in the journal Temperature, which described it as "a stress-related, psychosomatic disease." The author of the paper, Takakazu Oka, MD, explained that some people's "high core body temperatures" could be a result of "psychological stress."

"Some patients develop a high fever when they are exposed to emotional events, whereas others show a persistent low-grade fever lasting months and even years, either during or after situations of chronic stress," Dr. Oka explained.

Dr. Oka added that, for patients experiencing psychogenic fever, "there is no abnormal finding to account for" their high body temperature, aside from stress. "Moreover, there are still physicians who do not recognize the fact that psychological stress can cause high" body temperature," the 2015 paper said.

The paper acknowledged that "the mechanism for psychogenic fever is not yet fully understood," but added that studies conducted on animals had shown that psychological stress can raise the subjects' body temperatures. Dr. Oka explained that some people, when exposed to"emotional events," can develop a fever of 105.8°F. However, others exposed to emotional events "show a persistent low-grade fever," which is categorized as anything from 98.6°F to 100.4°F.

A few case report—individual examples—on psychogenic fever came out after that 2015 paper. For example, an August 2021 paper published in Clinical Case Reports described a 46-year-old man diagnosed with psychogenic fever due to worry about COVID-19. A March 2021 paper published in the Journal of Surgical Case Reports described a 58-year-old woman diagnosed with psychogenic fever ahead of a surgical procedure.

But more and larger-scale research was needed, as of April 2022, to truly confirm the psychogenic fever diagnosis and understand its potential mechanisms.

What Can I Do if I Get a Fever?

Since stress wasn't well-documented as an official cause of fever by April 2022, you don't need to chalk up a higher body temperature to stress of any kind. If you have a fever, consider setting up an appointment with your healthcare provider to find out what's causing it.

If you are experiencing other symptoms in addition to fever, such as difficulty breathing or cough, don't hesitate to go to the emergency room or an urgent care clinic. These could be symptoms of a disease such as COVID-19, according to the CDC.