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Acetaminophen Dosage

Applies to the following strength(s): 160 mg80 mg/0.8 mL160 mg/5 mL500 mg650 mg80 mg325 mg500 mg/15 mL120 mg120 mg/5 mL80 mg/5 mL10 mg/mL650 mg/25 mL80 mg/mL500 mg/5 mL48 mg/mL

The information at Drugs.com is not a substitute for medical advice. ALWAYS consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Fever

Immediate-release formulations:

Weight 50 kg or greater: 1000 mg IV or orally every 6 hours OR 650 mg IV, orally, or rectally every 4 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 4000 mg

Weight less than 50 kg: 15 mg/kg IV, orally, or rectally every 6 hours OR 12.5 mg/kg IV, orally, or rectally every 4 hours
Maximum Single Dose: 15 mg/kg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 75 mg/kg

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

Comments:
-This drug may be given as a single dose or at repeated intervals not to exceed maximum daily dose; maximum daily dose is based on all routes of administration and all products containing acetaminophen.
-For IV administration, verify the dose in mg and mL to ensure the dose is correct; verify that infusion pumps are properly programmed

Uses: For the management of mild to moderate pain and the management of moderate to severe pain with adjunctive opioid analgesics. For the reduction of fever.

Usual Adult Dose for Pain

Immediate-release formulations:

Weight 50 kg or greater: 1000 mg IV or orally every 6 hours OR 650 mg IV, orally, or rectally every 4 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 4000 mg

Weight less than 50 kg: 15 mg/kg IV, orally, or rectally every 6 hours OR 12.5 mg/kg IV, orally, or rectally every 4 hours
Maximum Single Dose: 15 mg/kg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 75 mg/kg

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

Comments:
-This drug may be given as a single dose or at repeated intervals not to exceed maximum daily dose; maximum daily dose is based on all routes of administration and all products containing acetaminophen.
-For IV administration, verify the dose in mg and mL to ensure the dose is correct; verify that infusion pumps are properly programmed

Uses: For the management of mild to moderate pain and the management of moderate to severe pain with adjunctive opioid analgesics. For the reduction of fever.

Usual Pediatric Dose for Fever

Age less than 2 years (off-label): 10 to 15 mg/kg orally every 4 to 6 hours on advice of physician; do not exceed 5 doses in 24 hours

Suppositories:
6 to 11 months: 80 mg rectally every 6 hours up to a maximum of 4 doses in 24 hours
12 to 36 months: 80 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours

Age: 2 to 12 years:
15 mg/kg IV, orally, or rectally every 6 hours or 12.5 mg/kg IV, orally, or rectally every 4 hours
Maximum Single Dose: 15 mg/kg; not to exceed 750 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 75 mg/kg in 24 hours; not to exceed 3750 mg

Age: 12 years or older:
Weight less than 50 kg: 15 mg/kg IV, orally, or rectally every 6 hours OR 12.5 mg/kg IV, orally, or rectally every 4 hours
Maximum Single Dose: 15 mg/kg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 75 mg/kg in 24 hours

Age 12 years or older:
Weight 50 kg or greater: 1000 mg IV or orally every 6 hours OR 650 mg IV, orally, or rectally every 4 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 4000 mg

Extended-release:
12 years or older: 1300 mg orally every 8 hours
Maximum daily dose: 3900 mg

Comments:
-This drug may be given as a single dose or at repeated intervals not to exceed maximum daily dose; maximum daily dose is based on all routes of administration and all products containing acetaminophen.
-For IV administration, the dose should be verified in mg and mL and necessary steps should be taken to ensure that infusion pumps are properly programmed.

Uses: For the management of mild to moderate pain and the management of moderate to severe pain with adjunctive opioid analgesics. For the reduction of fever.

Usual Pediatric Dose for Pain

Age less than 2 years (off-label): 10 to 15 mg/kg orally every 4 to 6 hours on advice of physician; do not exceed 5 doses in 24 hours

Suppositories:
6 to 11 months: 80 mg rectally every 6 hours up to a maximum of 4 doses in 24 hours
12 to 36 months: 80 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours

Age: 2 to 12 years:
15 mg/kg IV, orally, or rectally every 6 hours or 12.5 mg/kg IV, orally, or rectally every 4 hours
Maximum Single Dose: 15 mg/kg; not to exceed 750 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 75 mg/kg in 24 hours; not to exceed 3750 mg

Age: 12 years or older:
Weight less than 50 kg: 15 mg/kg IV, orally, or rectally every 6 hours OR 12.5 mg/kg IV, orally, or rectally every 4 hours
Maximum Single Dose: 15 mg/kg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 75 mg/kg in 24 hours

Age 12 years or older:
Weight 50 kg or greater: 1000 mg IV or orally every 6 hours OR 650 mg IV, orally, or rectally every 4 hours
Maximum Single Dose: 1000 mg
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose (includes all routes of administration and all acetaminophen-containing products): 4000 mg

Extended-release:
12 years or older: 1300 mg orally every 8 hours
Maximum daily dose: 3900 mg

Comments:
-This drug may be given as a single dose or at repeated intervals not to exceed maximum daily dose; maximum daily dose is based on all routes of administration and all products containing acetaminophen.
-For IV administration, the dose should be verified in mg and mL and necessary steps should be taken to ensure that infusion pumps are properly programmed.

Uses: For the management of mild to moderate pain and the management of moderate to severe pain with adjunctive opioid analgesics. For the reduction of fever.

Renal Dose Adjustments

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

Liver Dose Adjustments

Severe hepatic impairment: Use is contraindicated
Mild to moderate hepatic impairment: Use with caution; a reduced total daily dose may be warranted

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

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.

Oral Formulations:
Pediatric over-the-counter (OTC) weight-based dosing;
-Take 1 dose every 4 hours as needed while symptoms last
-Do not take more than 5 doses in 24 hours
-To determine dose, use weight first, if possible, otherwise use age:
Weight: Under 24 pounds: Consult physician
Weight: 24 to 35 pounds: 160 mg
Weight 36 to 47 pounds: 240 mg
Weight 48 to 59 pounds: 320 mg
Weight 60 to 71 pounds: 400 mg
Weight 72 to 95 pounds: 480 mg

Age: Under 2 years: Consult physician
Age: 2 to 3 years: 160 mg
Age: 4 to 5 years: 240 mg
Age: 6 to 8 years:: 320 mg
Age: 9 to 10 years:: 400 mg
Age: 11 years: 480 mg

Suspected Overdose:
-If an overdose is suspected, obtain a serum drug level as soon as possible, but no sooner than 4 hours after oral ingestion.
-Liver function studies should be obtained and repeated at 24-hour intervals.
-The antidote, N-acetylcysteine (NAC) should be administered as soon as possible according to NAC protocols.

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
- the dose in milligrams (mg) and milliliters (mL) is not confused;
- the dosing is based on weight for patients under 50 kg;
- infusion pumps are properly programmed;
-the total daily dose of acetaminophen from all sources does not exceed maximum daily limits.

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:
-More than maximum daily dose is taken in 24 hours
-This product is taken with other drugs containing acetaminophen
-Consume 3 or more alcoholic drinks every day while using this product.

US OVER THE COUNTER LABELING: Adults and children under 12 years of age:
This product contains acetaminophen. Severe liver damage may occur if:
-Adult takes more than maximum daily dose is taken in 24 hours
-Child takes more than 5 doses in 24 hours
-This product is taken with other drugs containing acetaminophen
-Adult consumes 3 or more alcoholic drinks every day while using this product.

Safety and efficacy have not been established in patients younger than 2 years.

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:
-When calculating daily acetaminophen doses, be sure to account for all acetaminophen-containing products and all routes of administration; do not exceed maximum doses.

Chewable tablets:
-Chew tablets before swallowing

Extended-release:
-Swallow whole; do not crush, chew, split, or dissolve

Oral disintegrating tablets:
-Allow to dissolve in mouth or chew before swallowing

Oral suspension:
-Shake well before using
-Use enclosed measuring device to measure dose

Parenteral:
-Infuse IV over 15 minutes; ensure infusion pumps are properly programmed
-Monitor end of infusion in order to prevent the possibility of an air embolism, especially in cases where this is the primary infusion.
Suppositories: For rectal use only
-Remove wrapper
-Carefully insert suppository well up into the rectum

Reconstitution/preparation techniques:
-For IV doses of 1000 mg: May administer without further dilution; may administer by inserting a vented IV set through the septum of the vial.
-For doses less than 1000 mg: Withdraw the appropriate dose from the vial and place in a separate empty, sterile container (e.g., glass bottle, plastic IV container, or syringe) for IV infusion.
- Administer within 6 hours of penetrating the vacuum seal of the glass vial.
-Do not use if particulate matter or discoloration is observed.
-Do not add other medications to the acetaminophen solution.

IV compatibility:
-Diazepam and chlorpromazine hydrochloride are physically incompatible

Storage requirements:
-IV: Single use only; store at 20C to 25C (68F to 77F); do not refrigerate or freeze

General:
-Drug-induced hepatotoxicity is preventable; all patients and caregivers need to be educated on how give/ take this drug safely and what to do if more than the recommended dose is consumed.
-Use of more than 1 acetaminophen-containing product at one time should be discouraged.
-Hypersensitivity reactions and serious rashes have been reported.

Monitoring:
-Monitor for nausea, vomiting, loss of appetite, sweating, extreme tiredness, unusual bleeding or bruising, pain in upper right part of the stomach, yellow of the skin or eyes, and/or flu-like symptoms as this may be an indication of overdose.
-Monitor for skin reactions

Patient advice:
-Patients should be advised to follow package directions for over the counter acetaminophen products including observing the maximum single dose and maximum daily dose limits.
-Patients should be discouraged from using multiple acetaminophen containing products concurrently.
-Patients should be advised that severe liver damage may occur if more than the recommended amount of this drug is taken; patients should seek medical help promptly if they suspect they have taken too much of this drug or if they experience nausea, vomiting, loss of appetite, or yellowing of the skin or eyes.
-Patients should be advised to limit alcohol use while taking this drug.

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