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Acetaminophen Dosage

Medically reviewed by Drugs.com. Last updated on Jan 16, 2024.

Applies to the following strengths: 160 mg; 80 mg/0.8 mL; 160 mg/5 mL; 500 mg; 650 mg; 80 mg; 325 mg; 500 mg/15 mL; 120 mg; 120 mg/5 mL; 325 mg/10.15 mL; 650 mg/20.3 mL; 10 mg/mL; 80 mg/5 mL; 650 mg/25 mL; 80 mg/mL; 500 mg/5 mL; 48 mg/mL

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Fever

Doses may be given as a single or repeated dose as follows:

Parenteral:
Weight 50 kg or greater: 1000 mg IV every 6 hours OR 650 mg IV every 4 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Dose: 4000 mg per 24 hours

Weight less than 50 kg: 15 mg/kg IV every 6 hours OR 12.5 mg/kg IV every 4 hours
Maximum Single Dose: 15 mg/kg
Minimum Dosing Interval: every 4 hours
Maximum Dose: 75 mg/kg per 24 hours

Oral:
Immediate-release: 325 mg to 1 g orally every 4 to 6 hours
Minimum Dosing Interval: every 4 hours
Maximum Single Dose: 1000 mg
Maximum Dose: 4 g per 24 hours

Extended-Release: 1300 mg orally every 8 hours
Maximum dose: 3900 mg per 24 hours

Rectal:
650 mg rectally every 4 to 6 hours
Maximum dose: 3900 mg per 24 hours

Comments:


Uses:

Usual Adult Dose for Pain

Doses may be given as a single or repeated dose as follows:

Parenteral:
Weight 50 kg or greater: 1000 mg IV every 6 hours OR 650 mg IV every 4 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Dose: 4000 mg per 24 hours

Weight less than 50 kg: 15 mg/kg IV every 6 hours OR 12.5 mg/kg IV every 4 hours
Maximum Single Dose: 15 mg/kg
Minimum Dosing Interval: every 4 hours
Maximum Dose: 75 mg/kg per 24 hours

Oral:
Immediate-release: 325 mg to 1 g orally every 4 to 6 hours
Minimum Dosing Interval: every 4 hours
Maximum Single Dose: 1000 mg
Maximum Dose: 4 g per 24 hours

Extended-Release: 1300 mg orally every 8 hours
Maximum dose: 3900 mg per 24 hours

Rectal:
650 mg rectally every 4 to 6 hours
Maximum dose: 3900 mg per 24 hours

Comments:


Uses:

Usual Pediatric Dose for Pain

Doses may be given as a single or repeated dose as follows:

PARENTERAL:
AGE: 2 to 12 years:


AGE: 13 years or older:
Maximum Single Dose: 15 mg/kg; not to exceed 750 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose: 75 mg/kg in 24 hours; not to exceed 3750 mg
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose: 4000 mg in 24 hours

ORAL: 10 to 15 mg/kg orally every 4 to 6 hours as needed not to exceed 5 doses in 24 hours
Weight: 2.7 to 5.3 kg (0 to 3 months): 40 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 5.4 to 8.1 kg (4 to 11 months): 80 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 8.2 to 10.8 kg (12 to 23 months): 120 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 10.9 to 16.3 kg (2 to 3 years): 160 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 16.4 to 21.7 kg (4 to 5 years): 240 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 21.8 to 27.2 kg (6 to 8 years): 320 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 27.3 to 32.6 kg (9 to 10 years): 400 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 32.7 to 43.2 kg (11 to 12 years): 480 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours

AGE: 12 years or older:
Immediate-release: 325 mg to 1 g orally every 4 to 6 hours
Minimum Dosing Interval: every 4 hours
Maximum Single Dose: 1000 mg
Maximum Dose: 4 g per 24 hours

Extended-Release: 1300 mg orally every 8 hours
Maximum dose: 3900 mg per 24 hours

RECTAL:
Age: 6 to 11 months: 80 mg rectally every 6 hours up to a maximum of 4 doses in 24 hours
Age: 12 to 36 months: 80 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
Age: 3 to 6 years: 120 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
Age: 6 to 12 years: 325 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
Age: 12 years or older: 650 mg rectally every 4 to 6 hours up to a maximum of 6 doses in 24 hours

Comments:

Uses:

Usual Pediatric Dose for Fever

Doses may be given as a single or repeated dose as follows:

PARENTERAL:
Neonates (including those premature neonates born at 32 weeks gestational age or later, up to 28 days chronological age): 12.5 mg/kg IV every 6 hours
Minimum Dosing Interval: 6 hours
Maximum Daily Dose: 50 mg/kg/day

Infants (29 days to 2 years old): 15 mg/kg every 6 hours
Minimum Dosing Interval: 6 hours
Maximum Daily Dose: 60 mg/kg/day

Age: 2 to 12 years: 12.5 mg/kg IV every 4 hours OR 15 mg/kg IV every 6 hours
Maximum Single Dose: 15 mg/kg; not to exceed 750 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose: 75 mg/kg in 24 hours; not to exceed 3750 mg

Age: 13 years or older; weight less than 50 kg: 12.5 mg/kg IV every 4 hours OR 15 mg/kg IV every 6 hours
Maximum Single Dose: 15 mg/kg; not to exceed 750 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose: 75 mg/kg in 24 hours; not to exceed 3750 mg

Age: 13 years or older; weight 50 kg or greater: 650 mg IV every 4 hours OR 1000 mg IV every 6 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose: 4000 mg in 24 hours

ORAL: 10 to 15 mg/kg orally every 4 to 6 hours as needed not to exceed 5 doses in 24 hours

Weight: 2.7 to 5.3 kg (0 to 3 months): 40 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 5.4 to 8.1 kg (4 to 11 months): 80 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 8.2 to 10.8 kg (12 to 23 months): 120 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 10.9 to 16.3 kg (2 to 3 years): 160 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 16.4 to 21.7 kg (4 to 5 years): 240 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 21.8 to 27.2 kg (6 to 8 years): 320 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 27.3 to 32.6 kg (9 to 10 years): 400 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours
Weight: 32.7 to 43.2 kg (11 to 12 years): 480 mg orally every 4 hours as needed not to exceed 5 doses in 24 hours

12 years or older:
Immediate-release: 325 mg to 1 g orally every 4 to 6 hours
Minimum Dosing Interval: every 4 hours
Maximum Single Dose: 1000 mg
Maximum Dose: 4 g per 24 hours

RECTAL:
Age: 6 to 11 months: 80 mg rectally every 6 hours up to a maximum of 4 doses in 24 hours
Age: 12 to 36 months: 80 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
Age: 3 to 6 years: 120 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
Age: 6 to 12 years: 325 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
Age: 75012 years or older: 650 mg rectally every 4 to 6 hours up to a maximum of 6 doses in 24 hours

Comments:

Use: For the reduction of fever.

Renal Dose Adjustments

Severe renal impairment (CrCl less than 30 mL/min): Use caution; longer dosing intervals and a reduced total daily dose may be warranted

Liver Dose Adjustments

Parenteral:
Severe hepatic impairment, severe active hepatic disease: Use is contraindicated
Mild to moderate hepatic impairment, mild to moderate active hepatic disease: Use with caution; a reduced total daily dose may be warranted

Over the counter products must contain labeling that states:
This product contains acetaminophen. Severe liver damage may occur if:

Dose Adjustments

Use caution in patients with alcoholism, chronic malnutrition, severe hypovolemia (e.g. due to dehydration or blood loss); A reduced daily dose may be warranted.

Suspected Overdose:

Precautions

US BOXED WARNING: RISK OF MEDICATION ERRORS
Take care when prescribing, preparing, and administering IV acetaminophen injection to avoid dosing errors which could result in accidental overdose and death. In particular, be careful to ensure that


US BOXED WARNING: HEPATOTOXICITY:
This drug has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed the maximum daily limits, and often involve more than 1 acetaminophen-containing product.

US OVER THE COUNTER LABELING: Adults only:
This product contains acetaminophen. Severe liver damage may occur if:

US OVER THE COUNTER LABELING: Adults and children under 12 years of age:
This product contains acetaminophen. Severe liver damage may occur if:

CONTRAINDICATIONS:

Safety and efficacy for the treatment of acute pain have not been established in patients younger than 2 years; the safety and effectiveness for treatment of fever in pediatric patients, including premature neonates born at 32 weeks or later, has been demonstrated in clinical trials.

Consult WARNINGS section for additional precautions.

Dialysis

Children:
Intermittent hemodialysis or peritoneal dialysis: Administer every 8 hours
CRRT: No adjustments necessary

Adults:
Intermittent hemodialysis or peritoneal dialysis: No adjustment necessary
CRRT: Administer every 8 hours

Other Comments

Administration advice:


Chewable tablets:

Extended-release:

Oral disintegrating tablets:

Oral suspension:

Parenteral:

Suppositories:

Reconstitution/preparation techniques:

IV compatibility:

Storage requirements:

General:

Monitoring:

Patient advice:

Frequently asked questions

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.