Most fevers break on their own within a few days, and the best thing you can do at home is stay hydrated, rest, and use over-the-counter medication if you’re uncomfortable. A fever is your body’s deliberate response to infection, not a malfunction, so the goal isn’t always to eliminate it completely. It’s to keep yourself comfortable and safe while your immune system does its job.
Why Your Body Runs a Fever
When you get sick, your brain’s internal thermostat (located in the hypothalamus) deliberately raises your body’s target temperature. Your body then works to reach that new, higher set point: blood vessels constrict to trap heat, your metabolism speeds up to generate more warmth, and you may start shivering. That’s why you feel cold and reach for blankets even though your temperature is rising.
This process is intentional and, up to a point, helpful. At higher temperatures, bacteria and viruses replicate less efficiently while your immune system ramps up. A temperature around 40°C (104°F) can boost your body’s production of antiviral proteins by roughly tenfold, and temperatures in the 39 to 40°C range have been shown to reduce the replication of certain viruses by more than a hundredfold. Fever also accelerates tissue repair and enhances the ability of immune cells to seek out and destroy infected cells. So a moderate fever is your body fighting back effectively.
Stay Hydrated
Fever increases water loss through your skin. For every degree Celsius above 38°C (100.4°F), your body loses roughly 10% more water through evaporation than it normally would. Over the course of a day or two, that adds up fast, especially if you’re also sweating, vomiting, or not eating much.
Water is the foundation, but if you’ve been feverish for more than a day or you’re sweating heavily, you also need to replace electrolytes. Broth, diluted juice, oral rehydration solutions, or sports drinks all work. Sip frequently rather than trying to drink large amounts at once, particularly if your stomach is unsettled. Dark urine or dizziness when standing are signs you’re already behind on fluids.
Use Over-the-Counter Fever Reducers
Acetaminophen and ibuprofen are the two standard options. For adults and children 12 and older, combination tablets containing 250 mg of acetaminophen and 125 mg of ibuprofen can be taken every eight hours, up to six tablets per day. If you’re taking acetaminophen alone, the absolute ceiling is 4,000 mg (4 grams) in 24 hours, though staying well below that limit is safer for your liver.
You don’t need to treat every fever with medication. If your temperature is mildly elevated but you feel fine, you can let it run its course. The main reason to take a fever reducer is comfort: headache, body aches, chills, or difficulty sleeping. If the fever is making you miserable, there’s no benefit to toughing it out.
Dress Light and Keep the Room Cool
When you’re chilled from a fever, bundling up in heavy blankets feels instinctive. But trapping too much heat can push your temperature higher. Wear lightweight, breathable clothing and use a single light blanket if you need one. Keep your room at a comfortable temperature rather than cranking up the heat.
If you’re actively shivering, it’s fine to add a layer until the shivering stops. Shivering is your body generating heat to reach its new set point, and forcing yourself to be cold while shivering can actually raise your core temperature further. Once the shivering passes and you feel warm, remove the extra layer.
Lukewarm Sponge Baths
A sponge bath with lukewarm water, around 32 to 35°C (90 to 95°F), can help bring your skin temperature down and provide some relief. Focus on the forehead, neck, and armpits. Never use cold water, ice, or rubbing alcohol. Cold water causes blood vessels to constrict and can trigger shivering, which works against you by generating more internal heat. If shivering starts during a sponge bath, stop immediately and let your body warm up.
How to Track Your Temperature
Rectal thermometers give the most accurate reading but are impractical for most adults. Oral thermometers are reliable for everyday use. Forehead (temporal) thermometers are convenient but can be thrown off by sweating, direct sunlight, or cold air. Ear thermometers work well for older children and adults but are unreliable for infants under seven months because of the shape of the ear canal.
The key is consistency. Pick one method and stick with it so you can track whether your temperature is trending up or down. Readings from different body sites don’t convert neatly to one another, so comparing an oral reading from this morning to a forehead reading tonight won’t give you useful information.
When a Fever Needs Medical Attention
For most healthy adults, a fever under 103°F (39.4°C) that lasts a day or two is not dangerous. Treat the symptoms and wait it out. But certain situations change the calculus significantly:
- Infants under 3 months: Any rectal temperature of 100.4°F (38°C) or higher requires an immediate call to your pediatrician. Young infants can’t mount the same immune response as older children, and fever at this age can signal serious infection.
- Children under 2 years: A fever of 102°F or higher warrants a call to your doctor within 24 hours, even if the child seems otherwise okay.
- Any child reaching 105°F (40.6°C): This is a medical emergency per the American Academy of Pediatrics. Seek care immediately.
- Adults with a fever above 103°F that doesn’t respond to medication, or any fever lasting more than three days, should be evaluated.
- Fever with specific symptoms: Stiff neck, confusion, difficulty breathing, persistent vomiting, or a rash that doesn’t fade when pressed all warrant urgent evaluation regardless of the temperature number.
What Not to Do
Aspirin should never be given to children or teenagers with a fever. It’s linked to a rare but serious condition affecting the liver and brain. Alcohol baths are an old home remedy that can cause dangerous drops in temperature and skin absorption of alcohol, especially in children. “Starving a fever” has no scientific basis. Your body needs fuel and fluids to mount an immune response, so eat when you can, even if it’s just toast or soup.
Avoid the urge to aggressively cool yourself with ice baths or freezing showers. Your hypothalamus has set a target temperature, and if you force your skin temperature down too fast, your body will fight back with shivering and vasoconstriction, potentially making you feel worse and driving your core temperature up rather than down.