Most fevers don’t need aggressive treatment. A fever is your immune system’s way of fighting infection, and the most effective relief combines staying hydrated, resting, and using over-the-counter medication when discomfort becomes hard to manage. A temperature of 100.4°F (38°C) or higher counts as a fever, whether measured orally, rectally, or by ear.
Why Your Body Runs a Fever
When your immune cells detect an infection, they trigger a chain reaction that ultimately raises your body’s temperature set point. Signaling molecules travel to the brain’s thermoregulatory center, which responds by ramping up heat production in fat tissue and constricting blood vessels near the skin to prevent heat loss. That’s why you feel chilled and shivery even though your temperature is climbing.
This temperature increase isn’t random. A rise of 1 to 4°C improves survival and resolution of many infections. Fever-range heat boosts the germ-killing activity of white blood cells, enhances the ability of immune cells to engulf and destroy pathogens, and speeds the movement of immune cells to lymph nodes where they coordinate a broader defense. In short, a moderate fever is your body doing its job. That’s why many doctors recommend treating the discomfort of a fever rather than trying to eliminate the fever itself.
Fluids Come First
Fever increases fluid loss through sweating and faster breathing. Dehydration makes you feel worse and can slow recovery. General daily recommendations are about 15 cups of fluid for men and 11 cups for women, but during a fever you’ll likely need more. Water, broth, diluted juice, and oral rehydration solutions all work.
If nausea makes drinking difficult, take small sips of about 30 ml (one ounce) every three to five minutes rather than gulping a full glass. This keeps fluid moving in without overwhelming your stomach. Watch for signs of dehydration: dark urine, dizziness, headache, rapid heart rate, or extreme thirst. In babies and young children, red flags include no wet diapers, rapid breathing, lethargy, or crying without tears.
Over-the-Counter Fever Reducers
Acetaminophen and ibuprofen are the two main options. Both lower fever by interrupting the chemical signaling that raises your temperature set point. They work slightly differently, so choosing between them often comes down to personal tolerance and any other health conditions you have.
Acetaminophen
Adults can take acetaminophen every 4 to 6 hours as needed, up to a maximum of 4,000 mg in 24 hours. Going over that limit risks severe liver damage, and in extreme cases, liver failure. Keep in mind that many combination cold and flu products already contain acetaminophen, so check every label to avoid accidentally doubling up. For children, dose by weight rather than age, and avoid giving it to infants under 8 weeks old. Children should receive no more than 5 doses in 24 hours.
Ibuprofen
Adults can take ibuprofen every 6 to 8 hours, with no more than 4 doses in 24 hours. Children over 95 pounds can take 500 to 650 mg per dose, staying under 4,000 mg daily. Do not give ibuprofen to infants under 6 months old unless directed by a pediatrician. Ibuprofen is harder on the stomach than acetaminophen, so taking it with food helps. Avoid aspirin entirely in children and teenagers because of the risk of a rare but serious condition called Reye’s syndrome.
Comfort Measures That Actually Help
Removing extra clothing and blankets is one of the simplest ways to let heat escape. When you’re feverish, the instinct is to bundle up because you feel cold, but piling on layers traps heat and can push your temperature higher. Dress in lightweight clothing and use a single light blanket if you need one.
Tepid sponging (using lukewarm water, not cold) can provide some additional relief, but the evidence is modest. A Cochrane review of the available research found limited evidence that sponging helps reduce fever, and its effect was clearest when used alongside acetaminophen rather than on its own. Sponging frequently causes shivering and discomfort, especially in children, which can be counterproductive since shivering generates more heat. If you try it, use comfortably warm water and stop if it’s making you or your child more miserable.
Never use rubbing alcohol on the skin to cool a fever. It can be absorbed through the skin, and in rare cases has caused loss of consciousness. Ice packs and cold baths are also poor choices because they trigger blood vessel constriction, which actually traps heat inside the body.
Fever in Children
Children spike fevers more frequently than adults, and the numbers can look alarming. A temperature of 104°F in a toddler with a common virus, while uncomfortable, isn’t automatically dangerous. Focus on how your child looks and acts rather than fixating on the number alone. A child who is still drinking fluids, making eye contact, and responsive between bouts of fussiness is generally handling the fever well.
Febrile seizures affect 2% to 5% of children in the U.S. and Europe, peaking between 12 and 18 months of age. These seizures are frightening to witness but almost never cause lasting neurological harm. Simple febrile seizures last under 15 minutes and resolve on their own. If a seizure lasts longer than 5 minutes, call 911. One important point: antipyretics like acetaminophen and ibuprofen have not been shown to prevent febrile seizures from happening, even though they lower temperature. A child who is prone to febrile seizures will sometimes seize regardless of fever treatment.
Warning Signs That Need Medical Attention
Most fevers resolve within a few days as the underlying infection clears. But certain symptoms alongside a fever point to something more serious.
In adults, seek immediate care for:
- Temperature of 103°F (39.4°C) or higher
- Stiff neck with pain when bending the head forward
- Severe headache or unusual sensitivity to bright light
- Mental confusion, altered speech, or strange behavior
- Persistent vomiting
- Difficulty breathing or chest pain
- Rash, especially one that doesn’t fade when pressed
- Convulsions or seizures
In children, contact a doctor if your child is listless or confused, has poor eye contact, vomits repeatedly, or has a fever lasting longer than three days. Any fever in an infant under 3 months old warrants a call to the pediatrician regardless of how the baby appears, because young infants can deteriorate quickly.