Acetaminophen

Topic Overview

Acetaminophen (such as Tylenol) reduces fever and relieves pain. It does not reduce inflammation, as do nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen, but it is less likely to cause stomach upset and other side effects.

Be sure to follow the nonprescription medicine precautions.

Dosage

• Adults: The usual dose is 325 mg to 650 mg. Take every 4 to 6 hours, as needed, up to 4 times in a 24-hour period. The maximum dose may vary from 3,000 mg to 4,000 mg, but do not take more than 4,000 mg in a 24-hour period. Follow all instructions on the label.
• Children: Check with your child's doctor or a pharmacist if your child is less than 2 years old or less than 24 pounds. Give acetaminophen every 4 hours as needed. Do not give more than 5 doses in a 24-hour period. Dosages are based on the child's weight. There are different acetaminophen products for infants and children.
  • Acetaminophen can be found in many forms and comes in different doses.
  • Be safe with medicines. Read and follow all instructions on the label.
  • Do not give your child more than the maximum dose recommended on the label.
  • Be careful when giving your child over-the-counter cold or flu medicines and acetaminophen (Tylenol) at the same time. Many of these medicines already contain acetaminophen. Too much acetaminophen can be harmful.
  • If you give medicine to your baby, follow your doctor's or pharmacist's advice about what amount to give. Do not use acetaminophen if your child is allergic to it.
  • Acetaminophen and ibuprofen are different products with different dosing recommendations. Talk to your child's doctor or a pharmacist before switching back and forth between doses of acetaminophen and ibuprofen. When you switch between two medicines, there is a chance your child will get too much medicine. Studies have not shown any added benefit from alternating these medicines.
  • Talk to your doctor or a pharmacist before you give medicine to reduce a fever in a baby who is 3 months of age or younger. This is to make sure a young baby's fever is not a sign of a serious illness. The exception is if your baby has just had an immunization. Fevers sometimes occur as a reaction to immunizations. After immunizations, you can give your baby medicine to reduce a fever.

Caution: Do not use this dose table with any other concentration of this medicine. Use only with the concentration of 160 mg in 5 mL. Check the label on your medicine to find the concentration.

Acetaminophen dose (160 mg in 5 mL) for your child's weight

Child's weight in pounds	Child's weight in kilograms	Dose in milligrams	Dose in milliliters
less than 11.0	less than 5.4	Ask a doctor or a pharmacist	Ask a doctor or a pharmacist
12.0-17.0	5.5-7.9	80 mg	2.5 mL
18.0-23.0	8.0-10.9	120 mg	3.75 mL
24.0-35.0	11.0-15.9	160 mg	5 mL
36.0-47.0	16.0-21.9	240 mg	7.5 mL
48.0-59.0	22.0-26.9	320 mg	10 mL
60.0-71.0	27.0-31.9	400 mg	12.5 mL
72.0-95.0	32.0-43.9	480 mg	15 mL

Side effects of acetaminophen are rare if it is taken in correct doses.

• Nausea and rash are the most common.
• High doses of acetaminophen can cause liver and kidney damage.

Reasons not to take acetaminophen

Do not take acetaminophen if you:

• Have liver disease.
• Drink alcohol heavily (3 or more drinks a day for men and 2 or more drinks a day for women).