Most fevers break on their own within a few days, but you can speed up relief with over-the-counter medications, proper hydration, and rest. A fever is any body temperature at or above 100.4°F (38°C), and in most cases it’s a sign your immune system is actively fighting an infection rather than something dangerous on its own.
Before trying to eliminate a fever entirely, it helps to know that moderate fevers actually serve a purpose. Elevated body temperature pushes pathogens out of their ideal growth range, while simultaneously boosting your immune cells’ ability to find and destroy invaders. That said, a fever that makes you miserable or climbs too high deserves treatment.
Over-the-Counter Fever Reducers
Acetaminophen (Tylenol) and ibuprofen (Advil, Motrin) are the two main options for bringing a fever down. Both work within about 30 to 60 minutes and last 4 to 6 hours per dose. You can take them individually or together in a single dose, which research shows is safe and effective as long as you stay within the daily limits for each.
For acetaminophen, the ceiling is 4,000 mg in 24 hours. Going above that risks serious liver damage. For ibuprofen, the upper limit is 2,400 mg in 24 hours. Follow the dosage instructions on your specific product’s packaging, since tablet strengths vary. If you’re alternating between the two medications rather than taking them together, spacing doses about 3 hours apart ensures you always have one working while the other wears off.
One critical rule: never give aspirin to children or teenagers. Aspirin has been linked to Reye’s syndrome, a rare but potentially life-threatening condition that causes swelling in the liver and brain, particularly when given during a viral illness like the flu or chickenpox. Stick with children’s acetaminophen or ibuprofen instead.
Dosing Fever Medicine for Children
Children’s doses are based on weight, not just age. If you know your child’s weight, use that to select the right amount from the dosing chart included with the medication. Liquid acetaminophen for children typically comes as 160 mg per 5 mL, and you should always measure it with the dosing syringe that comes in the box. Kitchen spoons are too imprecise and can easily lead to over- or underdosing.
For children under 12, acetaminophen can be given every 4 hours, with a maximum of 5 doses in 24 hours. Children over 12 can take extra-strength acetaminophen every 6 hours, up to 6 doses per day. Do not give extra-strength (500 mg) products to children under 12, or extended-release (650 mg) products to anyone under 18. Children under 2 should not receive acetaminophen at all without a doctor’s guidance.
Hydration Matters More Than You Think
Fever increases your body’s metabolic rate and causes you to lose fluid through sweat, even if you don’t feel like you’re sweating much. Dehydration makes you feel worse and can actually make it harder for your body to regulate temperature. Water is fine for most adults, but if you’ve also been dealing with vomiting or diarrhea, drinks with electrolytes (sodium and potassium are the key ones) help replace what you’re losing.
For infants and young children with fever, start with small amounts of an electrolyte solution like Pedialyte: about a teaspoon (5 mL) every 1 to 5 minutes, gradually increasing as the child tolerates it. Pushing too much fluid at once on a sick child often backfires and triggers vomiting.
Physical Cooling Methods
Tepid sponge baths are a common home remedy, but the evidence suggests they’re not particularly helpful. In a study of feverish young children, those who received a 15-minute sponge bath on top of acetaminophen cooled slightly faster in the first hour compared to children who only took acetaminophen. By two hours, there was no meaningful temperature difference between the groups. Worse, the children who were sponge-bathed showed significantly higher discomfort scores.
If you want to use physical cooling, a lukewarm (not cold) washcloth on the forehead or neck is unlikely to cause harm and may feel soothing. Avoid ice baths or rubbing alcohol on the skin, both of which can cause shivering that actually raises your core temperature, or in the case of alcohol, can be absorbed through the skin.
Rest and Environment
Your body fights infection most efficiently when it’s not diverting energy elsewhere. Sleep and rest genuinely accelerate recovery. Keep your room comfortably cool and dress in lightweight, breathable clothing. Bundling up under heavy blankets might feel instinctive when you have chills, but trapping too much heat can push your temperature higher. A single light blanket is enough if you’re feeling cold.
When a Fever Needs Medical Attention
For adults, a temperature of 103°F (39.4°C) or higher warrants a call to your doctor. At 104°F (40°C) or above, seek prompt medical attention. Any fever accompanied by a stiff neck, confusion, difficulty breathing, persistent vomiting, or an unusual rash needs immediate evaluation, regardless of the number on the thermometer.
Infants have tighter thresholds. A baby younger than 3 months with a rectal temperature of 100.4°F (38°C) or higher needs medical evaluation right away, even if they seem otherwise fine. For babies 3 to 6 months old, the concern level rises at 102°F (38.9°C), or at any temperature if the baby seems unusually irritable, sluggish, or uncomfortable. Children between 7 and 24 months should be seen if a fever above 102°F persists for more than a day, even without other symptoms.
Most fevers from common viral infections resolve within 3 to 5 days. If yours lingers beyond that, or if it goes away and then returns, that pattern is worth discussing with a healthcare provider since it can signal a secondary infection or a different underlying cause.