Drug Detail:Acetaminophen (Acetaminophen (oral))
Drug Class: Miscellaneous analgesics
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:
- Maximum daily dose is based on all routes of administration and all products containing acetaminophen.
- Maximum daily dose and dosing recommendations may differ by product; some manufacturers have decreased the maximum daily dose to protect consumers from inadvertent overdoses.
- 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
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:
- Maximum daily dose is based on all routes of administration and all products containing acetaminophen.
- Maximum daily dose and dosing recommendations may differ by product; some manufacturers have decreased the maximum daily dose to protect consumers from inadvertent overdoses.
- 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 Pain
Doses may be given as a single or repeated dose as follows:
PARENTERAL:
AGE: 2 to 12 years:
- Weight-based dosing: 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
Minimum Dosing Interval: every 4 hours
Maximum Daily Dose: 75 mg/kg in 24 hours; not to exceed 3750 mg
- Weight 50 kg or greater: 650 mg IV every 4 hours OR 1000 mg IV every 6 hours
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
- Alternatively, use weight first, then age:
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:
- Maximum daily dose is based on all routes of administration and all products containing acetaminophen.
- Maximum daily dose and dosing recommendations may differ by product; some manufacturers have decreased the maximum daily dose to protect consumers from inadvertent overdoses.
- 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 for the management of moderate to severe pain when used with adjunctive opioid analgesics.
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
- Alternatively, use weight first, then age:
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:
- Maximum daily dose is based on all routes of administration and all products containing acetaminophen.
- Maximum daily dose and dosing recommendations may differ by product; some manufacturers have decreased the maximum daily dose to protect consumers from inadvertent overdoses.
- For IV administration, verify the dose in mg and mL to ensure the dose is correct; verify that infusion pumps are properly programmed.
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:
- Adult takes more than maximum daily dose in 24 hours
- Child takes more than 5 doses in 24 hours
- More than 3 alcoholic drinks are consumed per day while using this product.
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:
- 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
- Three or more alcoholic drinks are consumer 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 in 24 hours
- Child takes more than 5 doses in 24 hours
- This product is taken with other drugs containing acetaminophen
- Persons consume 3 or more alcoholic drinks per day while using this product.
CONTRAINDICATIONS:
- Hypersensitivity to the active substance or any product excipients
- Severe hepatic impairment or severe active liver disease
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:
- 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 accurately 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
- Consult manufacturer product information for additional information
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 to 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.
- The effectiveness of IV administration for the treatment of acute pain in patients younger than 2 years has not been established.
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.
Frequently asked questions
- What's the best sore throat medicine to use?
- What medications cause liver enzymes to be elevated?
- Which painkiller should you use?
- What is paracetamol / panadol called in the US?
- Acetaminophen vs Ibuprofen: Which is better?
- How long does Percocet stay in your system?
- Can you take tramadol with acetaminophen, ibuprofen, or aspirin?
- Advil (ibuprofen) & Tylenol (acetaminophen) together, is it safe?
- Is it safe to take acetaminophen every day?
- How long does it take for Tylenol to start working?
- Is acetaminophen the same as Tylenol?
- Is Tylenol (acetaminophen) a blood thinner?
- Is acetaminophen (Tylenol) an NSAID Drug?
- Can you take paracetamol (acetaminophen) with antibiotics?
- Is Tylenol (acetaminophen) an anti-inflammatory drug?
