For most fevers with chills, acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) will bring your temperature down and ease the shivering. A fever is generally defined as a temperature above 100.4°F (38.0°C), and chills are your body’s natural response to reaching that new, higher temperature. Choosing the right medication, staying hydrated, and knowing when a fever needs medical attention are the key steps.
Why Fevers Cause Chills
Chills feel counterintuitive when your body is already hot, but they’re actually part of the heating process. During an infection, your immune system releases signaling molecules that act on the brain’s temperature control center, the hypothalamus. This resets your body’s thermostat to a higher target, sometimes 101°F, 102°F, or more. Because your actual body temperature is now below this new set point, your brain treats it like you’re cold. It triggers shivering, which is rapid muscle contraction designed to generate heat and push your temperature up to the new target.
Once your temperature reaches the new set point, the chills usually stop and you feel hot instead. When the infection starts to resolve (or you take a fever reducer), the set point drops back to normal and you begin sweating to cool down. This cycle of chills, fever, and sweating can repeat, especially with illnesses like the flu.
Best Medications for Adults
Two over-the-counter options work well for fever and chills in adults: acetaminophen and ibuprofen. Both lower the hypothalamic set point, which reduces your temperature and stops the shivering.
Acetaminophen is the most widely used fever reducer. The standard adult dose is 500 to 1,000 mg every 4 to 6 hours as needed. Do not exceed 4,000 mg (4 grams) in a 24-hour period. If you have liver disease or a history of heavy alcohol use, talk to your doctor before taking it, as it’s processed through the liver and can cause damage at high doses or with compromised liver function.
Ibuprofen reduces fever and also targets inflammation, which can help with body aches that often accompany chills. The typical adult dose is 200 to 400 mg every 4 to 6 hours. Ibuprofen is harder on the stomach and kidneys, so it should be avoided if you have kidney disease (especially advanced stages), heart failure, or a history of stomach ulcers or gastrointestinal bleeding. People with cardiovascular disease should also use caution, as ibuprofen and similar anti-inflammatory drugs can increase the risk of heart attack and stroke.
You can alternate between acetaminophen and ibuprofen if one alone isn’t controlling the fever. A combination tablet containing both (250 mg acetaminophen and 125 mg ibuprofen) is also available, taken as two tablets every 8 hours, with a maximum of six tablets per day. Aspirin is another option for adults, but avoid it if you have liver or kidney disease.
Fever Medication for Children
Children’s doses are based on weight, not age, so always check the packaging or ask a pharmacist. Liquid acetaminophen for children comes in a concentration of 160 mg per 5 mL. Use an oral syringe to measure it accurately, never a kitchen spoon. For children under 12, you can give a dose every 4 hours, up to 5 doses in 24 hours. Children over 12 can take extra-strength formulations every 6 hours, up to 6 doses per day.
Do not give acetaminophen to a child under 2 without guidance from a doctor. For babies under 12 weeks old, any fever needs immediate medical evaluation, as it can signal a serious infection.
Never give aspirin to children or teenagers. Aspirin use during a viral illness has been linked to Reye’s syndrome, a rare but serious condition that causes dangerous swelling in the liver and brain, and can lead to seizures, loss of consciousness, and organ failure.
Home Care Beyond Medication
Medication handles the temperature, but your body also needs support to fight off whatever is causing the fever.
Fluids are essential. Fever increases fluid loss through sweating and faster breathing. Drink water, diluted juice, or broth throughout the day. For children under 1, use an oral rehydration solution like Pedialyte, which replaces both water and electrolytes in the right proportions. Pedialyte ice pops can work well for toddlers who resist drinking.
Dress lightly. Your instinct during chills is to pile on blankets, but heavy layers can trap heat and push your temperature even higher once the chills pass. Wear light clothing, keep the room cool, and use a single sheet or light blanket. If the chills are intense, a light layer is fine temporarily, but remove it once the shivering stops.
Rest matters. Your immune system uses significant energy fighting infection. Sleep and rest let your body direct resources toward recovery rather than activity.
Warning Signs That Need Medical Attention
Most fevers resolve on their own within a few days. But certain symptoms alongside fever and chills signal something more serious.
In adults, get medical care right away if you experience:
- Difficulty breathing or shortness of breath
- Persistent pain or pressure in the chest or abdomen
- Confusion, persistent dizziness, or difficulty staying awake
- Seizures
- No urination (a sign of severe dehydration)
- Severe muscle pain or weakness
- A fever that improves but then returns and gets worse
In children, watch for fast or labored breathing, bluish lips or face, ribs pulling in with each breath, refusal to walk due to muscle pain, signs of dehydration (no urine for 8 hours, dry mouth, no tears), or a fever above 104°F that doesn’t respond to medication. Any fever in a baby under 12 weeks requires immediate evaluation.
A fever and cough that seem to be getting better but then spike again can indicate a secondary infection, like bacterial pneumonia following a viral illness. This pattern is worth a call to your doctor even if the individual symptoms feel manageable.