Acetaminophen & Ibuprofen Weight-Based Dosing


  • Acetaminophen and ibuprofen are equally effective in treating the symptoms of:
    • Fever
    • Pain
  • Ibuprofen is not safe for children less than 6 months of age.
  • Acetaminophen (e.g. Tylenol) can be given every 4 hours.
  • Ibuprofen (e.g. Motrin or Advil) can be given every 6 hours.
  • Please read our fever guide to understand the basics of fever management, and when you should be concerned.
  • Please read our guide to understand how fever in the first 90 days of life is different than for older babies and children.

Alternating Tylenol and Motrin

  • Only if your child is older than 6 months old.
  • You can alternate Tylenol and Motrin every 3 hours if you need to.
    • e.g. Motrin now, 3 hours later give Tylenol. 3 hours later give Motrin. 3 hours later give Tylenol, etc.
  • If your child's fussiness and discomfort are returning before they are due for another dose of tylenol or motrin, you can give a dose of the other type of medicine.
    • e.g. My child received tylenol at 2:00 pm, but the fussiness and discomfort have already returned by 5:00 pm. They can't receive another dose of tylenol until 6:00 pm (4 hours after the last dose), but you can give a dose of motrin now.
  • Never wake your child to give them a dose of fever medicine.

Weight-Based Dosing Table

Weight 6-11.9 lb 12-17.9 lb 18-23.9 lb 24-35.9 lb 36-47.9 lb 48-59.9lb 60-71.9 lb 72-95.9lb 96+ lb
Infant Acetaminophen
(e.g. Tylenol)
160 mg/5 ml
1.25ml (40mg) 2.5ml (80mg) 3.75ml (120mg) 5ml (160mg) 7.5ml (240mg) 10ml (320mg) 12.5ml (400mg) 15ml (480mg) 20ml (640mg)
Children’s Acetaminophen
(e.g. Tylenol)
160 mg/5 ml
1.25ml (40mg) 2.5ml (80mg) 3.75ml (120mg) 5ml (160mg) 7.5ml (240mg) 10ml (320mg) 12.5ml (400mg) 15ml (480mg) 20ml (640mg)
Rectal Acetaminophen
(e.g. FeverAll)
80 mg per 1 rectal suppository
1/2 supp.
1.0 supp.
1.5 supp.
2.0 supp.
----- ----- ----- ----- -----
Infant Ibuprofen
(e.g. Motrin or Advil)
50 mg/1.25 ml
n/a 1.25ml (50mg) 1.875ml (75mg) 2.5ml (100mg) 3.75ml (150mg) 5ml (200mg) 6.25ml
Children’s Ibuprofen
n/a 2.5ml (50mg) 4ml  (75mg) 5ml (100mg) 7.5ml (150mg) 10ml (200mg) 12.5ml (250mg) 15ml (300mg) 20ml (400mg)