Fevers are often caused by an infection in the body.
Although they are uncomfortable, fevers themselves are not usually harmful and can have some benefits.
Over-the-counter (OTC) medications used to break a fever can make you feel better. But they won’t cure the illness that caused the fever in the first place.
It can feel uncomfortable or even painful to have a fever. When you’re sick and your body temperature rises, you might flip between feeling hot and feeling cold — and between shivering and sweating — at a moment’s notice.
So, what should you do when you have a fever? Should you try to break it, or put up with the discomfort? It turns out that while a fever can be an important sign of illness, it isn’t usually a problem on its own. Keep reading to learn how to break a fever — and whether or not you should.
The normal human body temperature falls between about 97 and 99.5 degrees Fahrenheit (36.2 and 37.5 degrees Celsius). When your body heats itself up warmer than that, you have a fever.
Fever is usually caused by inflammation in your body. Typically, the inflammation comes from an infection, like the flu or strep throat. But immune-related diseases, cancer, and even some medications can cause a fever, too.
When there is a lot of Inflammation in your body, your immune system releases chemicals that turn up the set-point of your internal thermostat. This makes your body act in certain ways to make itself warmer. For example, a fever causes chills (shivers) because your body is trying to warm itself up — even though you’re not actually cold.
Over-the-counter (OTC) fever reducers work by interrupting the chemical signals that connect inflammation in your body to your internal thermostat.
Medications that stop or break a fever are called antipyretics. Many are available OTC without a prescription.
OTC antipyretics include:
Many people try to treat fevers by cooling the outside of the body. This is done by:
Giving a sponge bath
Taking a cool shower
Removing warm clothing or blankets
Rubbing alcohol on the skin
But cooling the outside of the body isn’t always a good idea. While it might bring the measured temperature down slightly, surface cooling doesn’t affect the temperature deep inside the body (the core temperature). In fact, this can cause the core temperature to rise even higher in response — which can feel quite unpleasant and make shivering worse.
It’s natural to want your fever to go away. But treating a fever doesn’t stop the infection that caused it — all it does is bring your temperature down. Even so, you might want to break your fever because:
A fever can make you feel low.
An extremely high fever (105 degrees or above) can cause damage to the body.
A fever can cause dehydration. This is because a higher body temperature makes the water in your breath and on your skin evaporate faster.
Fevers can make some people more likely to get a seizure.
It seems likely that fevers happen for a biological reason. After all, when we’re fighting an infection, our body uses extra energy to heat itself up — and this is true across many animal species. But why?
We don’t know have a full understanding yet, but here’s what scientists have learned so far:
Some germs, including the virus that causes COVID-19, slow down their growth when the temperature around them rises.
Our immune system is more efficient when our body temperature is higher.
A fever can weed out weak body cells — such as those damaged by an infection — and this might lower the amount of time you feel sick.
Aside from these natural benefits, fevers are helpful from a practical standpoint because:
The pattern of your fever can give clues about the illness that might be causing it. In other words, it can help you track whether infection is getting better or worse.
Many of our modern antibiotics work better at warmer temperatures.
While a fever isn’t always harmful, that doesn’t mean you should ignore it. After all, the fever is probably caused by an infection, and some infections can be serious.
There can be times when a fever requires medical attention. See a healthcare provider right away if:
An infant under 3 months old has a fever over 100.3 degrees.
An infant 3 to 12 months old has a fever above 102.2 degrees.
A child has a fever, and is unvaccinated.
You have a very high fever (105 degrees or higher).
You have had a fever for more than 3 days in a row.
You have a fever plus other symptoms, like weight loss, rash, cough, or difficulty breathing, that you can’t explain.
You’ve recently had surgery.
You have a fever and are immunosuppressed, have an immune deficiency, or are receiving chemotherapy.
You have an IV line, such as a PICC line, port, or central venous catheter.
You take drugs recreationally through an IV.
In general, if you have a fever, it’s best to stay home. Your infection could be contagious to others. In fact, it’s possible that the unpleasant feelings that come with a fever have an evolutionary cause: It makes you want to isolate yourself, which helps protect people around you.
Whether or not you choose to break a fever is up to you. While a fever can make you feel low, there might be good reasons to let a fever run its course. If you do choose to break your fever, antipyretic medications are effective — but remember, they won’t treat the infection that’s to blame.
While medication can help lower your temperature and relieve symptoms, it’s important to know when to get medical attention. This way, a healthcare provider can identify and treat the illness that may be causing your fever, and prevent further complications.
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