Acetaminophen

Name: Acetaminophen

What else should I know about acetaminophen?

What preparations of acetaminophen are available?
  • Solution/suspension: 160 mg/5 ml
  • Liquid: 500 mg/ml
  • Chewable tablets: 80, 160 m
  • Tablet (disintegrating) 80, 160 mg
  • Caplets: 325, 500, 650 mg
  • Caplet (extended release): 650 mg
  • Gelcaps: 500 mg
  • Geltabs: 500 mg
  • Suppository: 80, 120, 325, 650 mg
How should I keep acetaminophen stored?

Tablets and solutions should be stored at room temperature 15 C to 30 C (59 F to 86 F). Suppositories should be refrigerated between 2 C and 27 C (35 F and  80 F).

Acetaminophen Dosage and Administration

Administration

Usually administered orally; may be administered rectally as suppositories in patients who cannot tolerate oral therapy.207 222 226 227 228 Also may be administered IV.300

Oral Administration

Swallow extended-release tablets whole; do not crush, chew, or dissolve in liquid.222

Because combinations and dosage strengths vary for fixed-combination preparations, consult manufacturer’s product labeling for appropriate dosage of the specific preparation.

Pediatric Administration

For liquid preparations (e.g., solution, suspension), use the calibrated dosing device provided by the manufacturer for measurement of the dose.207 281

80-mg orally disintegrating tablets may be used in children ≥2 years of age.207 235

160-mg orally disintegrating tablets or 325-mg conventional tablets commonly used in children ≥6 years of age.207 222 235

Orally disintegrating tablets (e.g., Tylenol Meltaways) should be allowed to dissolve in the mouth or should be chewed before swallowing.237 Use caution to ensure that the correct number of tablets required for the intended dose is removed from the blister package.236 237

Rectal Administration

Dividing suppositories in an attempt to administer lower dosages may not provide a predictable dose.226

Some experts state that rectal acetaminophen preparations should not be used for self-medication in children unless such use is specifically discussed with a clinician and parents or caregivers are instructed to adhere to dosage and administration recommendations.226 227 228

IV Administration

For solution and drug compatibility information, see Compatibility under Stability.

Administer by IV infusion.300

Monitor the end of the infusion to prevent possibility of air embolism, especially when acetaminophen solution is the primary infusion.300

Commercially available 10-mg/mL injection may be administered without further dilution.300 Each vial (1 g/100 mL) is for single use only; discard any unused portions.300

Dose of 1 g: Administer by inserting a vented IV set through the septum of the 100-mL vial.300

Dose of <1 g: Dose must be withdrawn from vial and placed in a separate container for IV infusion to avoid inadvertent administration of the total volume of the vial.300 Aseptically withdraw the appropriate dose from an intact sealed vial and transfer to an empty sterile container (e.g., glass bottle, plastic container, syringe); draw small-volume (up to 60 mL) pediatric doses into a syringe and administer via syringe pump.300

Administer within 6 hours after penetration of the vacuum seal of the vial or transfer of vial contents to another container.300

Do not admix with any other drugs.300

Rate of Administration

Administer by IV infusion over 15 minutes.300

Dosage

To minimize risk of inadvertent overdosage, FDA recommends that health care providers stop prescribing and dispensing prescription combination preparations containing >325 mg of acetaminophen per dosage unit;286 287 doses consisting of either 1 or 2 dosage units (i.e., 325 or 650 mg of acetaminophen per dose) may be prescribed as clinically appropriate for the patient and in consideration of the strengths of each component (generally acetaminophen and an opiate analgesic) of the fixed combination.286 (See Preparations.)

FDA recommends that pharmacists receiving prescriptions for fixed-combination preparations containing >325 mg of acetaminophen per dosage unit contact the prescriber to discuss use of a preparation containing ≤325 mg of the drug per dosage unit.286 287

Take care to avoid dosing errors when prescribing, preparing, and administering IV acetaminophen.300 (See Boxed Warning.)

Pediatric Patients

Dosage in children should be guided by body weight.207 237 (See Pediatric Use under Cautions.)

Pain Oral

Dose may be given every 4–6 hours as necessary (up to 5 times in 24 hours).198 207 237

Dosage for Self-medication of Pain in Children up to 11 Years of Age207237279280

Age

Weight

Oral Dose

≤3 months

2.7–5 kg

40 mg

4–11 months

5–8 kg

80 mg

12–23 months

8–11 kg

120 mg

2–3 years

11–16 kg

160 mg

4–5 years

16–21 kg

240 mg

6–8 years

22–27 kg

320 mg

9–10 years

27–32 kg

400 mg

11 years

33–43 kg

480 mg

For self-medication in children ≥12 years of age, 650 mg every 4–6 hours or 1 g every 6 hours as necessary.222 278 (See Prescribing Limits under Dosage and Administration.)

Rectal

Dose may be given every 4–6 hours as necessary (up to 5 times in 24 hours).198

Dosage for Self-medication of Pain in Children 2–12 Years of Age198

Age

Rectal Dose

2–4 years

160 mg

4–6 years

240 mg

6–9 years

320 mg

9–11 years

320–400 mg

11–12 years

320–480 mg

Individualize dosage in children <2 years of age.226 227 228

For self-medication in children ≥12 years of age, 325–650 mg every 4 hours as necessary.198

IV

Administer as single or repeated doses.300

Children 2–12 years of age: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours.300

Adolescents ≥13 years of age and weighing <50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours.300

Adolescents ≥13 years of age and weighing ≥50 kg: 1 g every 6 hours or 650 mg every 4 hours.300 May switch between oral and IV acetaminophen without dosage adjustment.300

Fever Oral

Dose may be given every 4–6 hours as necessary (up to 5 times in 24 hours).198 207 237

Dosage for Self-medication of Fever in Children up to 11 Years of Age207237279280

Age

Weight

Oral Dose

≤3 months

2.7–5 kg

40 mg

4–11 months

5–8 kg

80 mg

12–23 months

8–11 kg

120 mg

2–3 years

11–16 kg

160 mg

4–5 years

16–21 kg

240 mg

6–8 years

22–27 kg

320 mg

9–10 years

27–32 kg

400 mg

11 years

33–43 kg

480 mg

For self-medication in children ≥12 years of age, 650 mg every 4–6 hours or 1 g every 6 hours as necessary.222 278 (See Prescribing Limits under Dosage and Administration.)

Rectal

Dose may be given every 4 hours as necessary (up to 5 times in 24 hours).198

Dosage for Self-medication of Fever in Children 2–12 Years of Age198

Age

Rectal Dose

2–4 years

160 mg

4–6 years

240 mg

6–9 years

320 mg

9–11 years

320–400 mg

11–12 years

320–480 mg

Individualize dosage in children <2 years of age.226 227 228

For self-medication in children ≥12 years of age, 325–650 mg every 4 hours as necessary.198

IV

Administer as single or repeated doses.300

Children 2–12 years of age: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours.300

Adolescents ≥13 years of age and weighing <50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours.300

Adolescents ≥13 years of age and weighing ≥50 kg: 1 g every 6 hours or 650 mg every 4 hours.300 May switch between oral and IV acetaminophen without dosage adjustment.300

Adults

Pain Oral

For self-medication, 650 mg every 4–6 hours or 1 g every 6 hours as necessary.222 278 Alternatively, 1.3 g as extended-release tablets every 8 hours.222 (See Prescribing Limits under Dosage and Administration.)

Rectal

325–650 mg every 4 hours as necessary.198

IV

Administer as single or repeated doses.300

Adults weighing ≥50 kg: 1 g every 6 hours or 650 mg every 4 hours.300 May switch between oral and IV acetaminophen without dosage adjustment.300

Adults weighing <50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours.300

Pain Associated with Migraine Headache Oral

Acetaminophen, aspirin, and caffeine for self-medication: 2 tablets (each containing acetaminophen 250 mg, aspirin 250 mg, and caffeine 65 mg) as a single dose.212

Pain Associated with Osteoarthritis Oral

1 g 4 times daily.149 a Alternatively, 1.3 g as extended-release tablets every 8 hours.199 200 201

Fever Oral

For self-medication, 650 mg every 4–6 hours or 1 g every 6 hours as necessary.222 278 (See Prescribing Limits under Dosage and Administration.)

Rectal

325–650 mg every 4 hours as necessary.198

IV

Administer as single or repeated doses.300

Adults weighing ≥50 kg: 1 g every 6 hours or 650 mg every 4 hours.300 May switch between oral and IV acetaminophen without dosage adjustment.300

Adults weighing <50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours.300

Prescribing Limits

Pediatric Patients

Pain Oral

Do not exceed recommended daily dosage.204 205 206 207 237 For self-medication in children ≥12 years of age, some manufacturers recommend a maximum dosage of 3 g daily.278 (See Prescribing Limits: Adults, under Dosage and Administration.)

Self-medication should not exceed 5 days (in children 2–11 years of age) or 10 days (in children ≥12 years of age).207 278 279 280

IV

Children 2–12 years of age: Maximum single dose is 15 mg/kg, minimum dosing interval is 4 hours, and maximum daily dosage is 75 mg/kg per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adolescents ≥13 years of age and weighing <50 kg: Maximum single dose is 15 mg/kg, minimum dosing interval is 4 hours, and maximum daily dosage is 75 mg/kg per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adolescents ≥13 years of age and weighing ≥50 kg: Maximum single dose is 1 g, minimum dosing interval is 4 hours, and maximum daily dosage is 4 g per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Fever Oral

Do not exceed recommended daily dosage.204 205 206 207 237 For self-medication in children ≥12 years of age, some manufacturers recommend a maximum dosage of 3 g daily.278 (See Prescribing Limits: Adults, under Dosage and Administration.)

Self-medication should not exceed 3 days.207 278 279 280

IV

Children 2–12 years of age: Maximum single dose is 15 mg/kg, minimum dosing interval is 4 hours, and maximum daily dosage is 75 mg/kg per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adolescents ≥13 years of age and weighing <50 kg: Maximum single dose is 15 mg/kg, minimum dosing interval is 4 hours, and maximum daily dosage is 75 mg/kg per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adolescents ≥13 years of age and weighing ≥50 kg: Maximum single dose is 1 g, minimum dosing interval is 4 hours, and maximum daily dosage is 4 g per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adults

Current limit is 4 g daily.197 198 222 Some experts recommend a maximum dosage of 3 g daily when used for long-term therapy (e.g., ≥2 weeks).243 FDA is evaluating whether data exist to support establishing a lower (i.e., <4 g daily) maximum daily dosage for certain patients (e.g., those who chronically ingest alcohol).245 246 Some manufacturers (e.g., McNeil, Tylenol) voluntarily revised their labeling and currently recommend a maximum dosage of 3 g daily.272 278

Pain Oral or Rectal

Maximum 4 g daily.198 222 Some manufacturers recommend a maximum oral dosage of 3 g daily.278 (See Prescribing Limits: Adults, under Dosage and Administration.)

Self-medication should not exceed 10 days.222

IV

Adults weighing ≥50 kg: Maximum single dose is 1 g, minimum dosing interval is 4 hours, and maximum daily dosage is 4 g per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adults weighing <50 kg: Maximum single dose is 15 mg/kg, minimum dosing interval is 4 hours, and maximum daily dosage is 75 mg/kg per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Pain Associated with Migraine Headache Oral

Acetaminophen, aspirin, and caffeine: Maximum for self-medication is 2 tablets (each containing acetaminophen 250 mg, aspirin 250 mg, and caffeine 65 mg) in 24 hours unless otherwise directed by a clinician.212

Pain Associated with Osteoarthritis Oral

Maximum 4 g daily.197

Fever Oral or Rectal

Maximum 4 g daily.198 222 Some manufacturers recommend maximum oral dosage of 3 g daily.278 (See Prescribing Limits: Adults, under Dosage and Administration.)

Self-medication should not exceed 3 days.222

IV

Adults weighing ≥50 kg: Maximum single dose is 1 g, minimum dosing interval is 4 hours, and maximum daily dosage is 4 g per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Adults weighing <50 kg: Maximum single dose is 15 mg/kg, minimum dosing interval is 4 hours, and maximum daily dosage is 75 mg/kg per 24-hour period (including all routes of administration and all acetaminophen-containing preparations, including fixed combinations).300

Special Populations

Hepatic Impairment

Reduction of total daily dosage may be warranted in patients with hepatic impairment or active liver disease.300 (See Hepatic Impairment under Cautions.)

Renal Impairment

Longer dosing intervals and reduced total daily dosage may be warranted in patients with severe renal impairment (Clcr ≤30 mL/minute).300

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Caplet, oral: 500 mg

Cetafen Extra: 500 mg

Mapap Extra Strength: 500 mg

Mapap Extra Strength: 500 mg [scored]

Pain Eze: 650 mg

Tylenol: 325 mg

Tylenol Extra Strength: 500 mg

Caplet, extended release, oral:

Mapap Arthritis Pain: 650 mg

Tylenol 8 HR Arthritis Pain: 650 mg

Capsule, oral:

Mapap Extra Strength: 500 mg

Tylenol: 325 mg

Tylenol Extra Strength: 500 mg

Injection, solution [preservative free]:

Ofirmev: 10 mg/mL (100 mL)

Liquid, oral: 160 mg/5 mL (120 mL, 473 mL); 500 mg/5 mL (240 mL)

Mapap Extra Strength: 500 mg/5 mL (237 mL) [contains propylene glycol, sodium 9 mg/15 mL, sodium benzoate; cherry flavor]

Q-Pap Children's: 160 mg/5 mL (118 mL [DSC], 473 mL [DSC]) [ethanol free; contains propylene glycol, sodium 2 mg/5 mL, sodium benzoate; cherry flavor, grape flavor]

Silapap Children's: 160 mg/5 mL (118 mL, 237 mL, 473 mL) [ethanol free, sugar free; contains propylene glycol, sodium benzoate; cherry flavor]

Tylenol Extra Strength: 500 mg/15 mL (240 mL [DSC]) [ethanol free; contains propylene glycol, sodium benzoate; cherry flavor]

Solution, oral: 160 mg/5 mL (5 mL, 10 mL, 20 mL)

Pain & Fever Children's: 160 mg/5 mL (118 mL, 473 mL) [ethanol free, sugar free; contains propylene glycol, sodium 1 mg/5 mL, sodium benzoate; cherry flavor]

Solution, oral [drops]: 80 mg/0.8 mL (15 mL [DSC])

Little Fevers: 80 mg/mL (30 mL [DSC]) [dye free, ethanol free, gluten free; contains propylene glycol, sodium benzoate; berry flavor]

Q-Pap Infants': 80 mg/0.8 mL (15 mL [DSC]) [ethanol free; contains propylene glycol; fruit flavor]

Silapap Infants': 80 mg/0.8 mL (15 mL [DSC], 30 mL [DSC]) [ethanol free; contains propylene glycol, sodium benzoate; cherry flavor]

Suppository, rectal: 120 mg (12s); 325 mg (12s); 650 mg (12s)

Acephen: 120 mg (12s, 50s, 100s); 325 mg (6s, 12s, 50s, 100s); 650 mg (12s, 50s, 100s)

FeverAll Adults: 650 mg (50s)

FeverAll Children's: 120 mg (6s, 50s)

FeverAll Infants': 80 mg (6s, 50s)

FeverAll Junior Strength: 325 mg (6s, 50s)

Suspension, oral: 160 mg/5 mL (5 mL, 10.15 mL, 20.3 mL)

Mapap Children's: 160 mg/5 mL (118 mL) [ethanol free; contains propylene glycol, sodium benzoate; cherry flavor]

Mapap Infants': 160 mg/5 mL (59 mL [DSC]) [dye free, ethanol free; contains propylene glycol, sodium benzoate; cherry flavor]

Nortemp Children's: 160 mg/5 mL (118 mL) [ethanol free; contains propylene glycol, sodium benzoate; cotton candy flavor]

Pain & Fever Children's: 160 mg/5 mL (60 mL) [ethanol free; contains propylene glycol, sodium benzoate; cherry flavor]

Q-Pap Children's: 160 mg/5 mL (118 mL [DSC]) [ethanol free; contains sodium 2 mg/5 mL, sodium benzoate; bubblegum flavor, cherry flavor, grape flavor]

Tylenol Children's: 160 mg/5 mL (120 mL) [dye free, ethanol free; contains propylene glycol, sodium benzoate; cherry flavor]

Tylenol Children's: 160 mg/5 mL (120 mL) [ethanol free; contains propylene glycol, sodium 2 mg/5 mL, sodium benzoate; bubblegum flavor]

Tylenol Children's: 160 mg/5 mL (60 mL, 120 mL) [ethanol free; contains propylene glycol, sodium 2 mg/5 mL, sodium benzoate; cherry flavor]

Tylenol Children's: 160 mg/5 mL (120 mL) [ethanol free; contains propylene glycol, sodium 2 mg/5 mL, sodium benzoate; grape flavor]

Tylenol Children's: 160 mg/5 mL (120 mL) [ethanol free; contains propylene glycol, sodium 2 mg/5 mL, sodium benzoate; strawberry flavor]

Tylenol Infants': 160 mg/5 mL (60 mL) [ethanol free; contains propylene glycol, sodium benzoate; grape flavor]

Syrup, oral:

Triaminic Children's Fever Reducer Pain Reliever: 160 mg/5 mL (118 mL) [contains benzoic acid, sodium 6 mg/5 mL; bubblegum flavor]

Triaminic Children's Fever Reducer Pain Reliever: 160 mg/5 mL (118 mL) [contains sodium 5 mg/5 mL, sodium benzoate; grape flavor]

Tablet, oral: 325 mg, 500 mg

Aspirin Free Anacin Extra Strength: 500 mg

Cetafen: 325 mg

Mapap: 325 mg

Mapap Extra Strength: 500 mg

Non-Aspirin Pain Reliever: 325 mg

Pharbetol: 325 mg

Pharbetol Extra Strength: 500 mg

Q-Pap: 325 mg [scored] [DSC]

Q-Pap Extra Strength: 500 mg [scored] [DSC]

Tylenol: 325 mg

Tylenol Extra Strength: 500 mg

Valorin: 325 mg [sugar free]

Valorin Extra: 500 mg [sugar free]

Tablet, chewable, oral: 80 mg

Mapap Children's: 80 mg [fruit flavor]

Tablet, dispersible, oral: 80 mg, 160 mg

Mapap Children's: 80 mg [bubblegum flavor]

Mapap Children's: 80 mg [grape flavor]

Tylenol Jr. Meltaways: 160 mg [bubblegum flavor] [DSC]

Tylenol Jr. Meltaways: 160 mg [grape flavor] [DSC]

Dosing Adult

Note: In 2011, McNeil Consumer Healthcare reduced the maximum doses and increased the dosing interval on the labeling of some of their acetaminophen OTC products used in older pediatric patients (usually children ≥ 12 years and adolescents) and adults in an attempt to protect consumers from inadvertent overdoses. For example, the maximum daily dose of Tylenol Extra Strength and Tylenol Regular Strength was decreased and the dosing interval for Tylenol Extra Strength was increased. Health care professionals may still prescribe or recommend the 4 g daily maximum to patients (but are advised to use their own discretion and clinical judgment) (McNeil Consumer Healthcare, 2014).

Pain or fever:

Oral: Note: OTC dosing recommendations may vary by product and/or manufacturer. When calculating the maximum daily dose, consider all sources of acetaminophen (prescription and OTC) and all routes of administration. Do not exceed the maximum recommended daily dose. No dose adjustment required when converting between different acetaminophen formulations.

Immediate-release:

Regular strength: 650 mg every 4 to 6 hours; maximum daily dose: 3250 mg daily unless directed by health care provider; under health care provider supervision, daily doses ≤4 g may be used

Extra strength: 1000 mg every 6 hours; maximum daily dose: 3000 mg daily unless directed by a health care provider; under health care provider supervision, daily doses ≤4 g may be used

Extended-release: 1300 mg every 8 hours; maximum daily dose: 3900 mg daily

Rectal: 650 mg every 4 to 6 hours; maximum daily dose: 3900 mg daily

IV:

<50 kg: 12.5 mg/kg every 4 hours or 15 mg/kg every 6 hours; maximum single dose: 15 mg/kg/dose (≤750 mg/dose); maximum daily dose: 75 mg/kg/day (≤3.75 g/day)

≥50 kg: 650 mg every 4 hours or 1,000 mg every 6 hours; maximum single dose: 1,000 mg/dose; maximum daily dose: 4 g/day

Adverse Reactions

Oral, Rectal: Frequency not defined:

Dermatologic: Skin rash

Endocrine & metabolic: Decreased serum bicarbonate, decreased serum calcium, decreased serum sodium, hyperchloremia, hyperuricemia, increased serum glucose

Genitourinary: Nephrotoxicity (with chronic overdose)

Hematologic & oncologic: Anemia, leukopenia, neutropenia, pancytopenia

Hepatic: Increased serum alkaline phosphatase, increased serum bilirubin

Hypersensitivity: Hypersensitivity reaction (rare)

Renal: Hyperammonemia, renal disease (analgesic)

IV:

>10%: Gastrointestinal: Nausea (adults: 34%; neonates, infants, children, and adolescents: ≥5%), vomiting (adults: 15%; neonates, infants, children, and adolescents: ≥5%)

1% to 10%:

Cardiovascular: Hypertension (≥1%), hypotension (≥1%), peripheral edema (adults: ≥1%), tachycardia

Central nervous system: Headache (adults: 10%; neonates, infants, children, and adolescents: ≥1%), insomnia (adults: 7%), agitation (neonates, infants, children, and adolescents: ≥1%), anxiety (adults: ≥1%), fatigue (adults: ≥1%), trismus (adults: ≥1%)

Dermatologic: Pruritus (neonates, infants, children, and adolescents: ≥5%), skin rash

Endocrine & metabolic: Hypoalbuminemia (neonates, infants, children, and adolescents: ≥1%), hypokalemia (≥1%), hypomagnesemia (neonates, infants, children, and adolescents: ≥1%), hypophosphatemia (neonates, infants, children, and adolescents: ≥1%), hypervolemia

Gastrointestinal: Constipation (neonates, infants, children, and adolescents: ≥5%), diarrhea (neonates, infants, children, and adolescents: ≥1%), abdominal pain

Genitourinary: Oliguria (neonates, infants, children, and adolescents: ≥1%)

Hematologic & oncologic: Anemia (≥1%)

Hepatic: Increased serum transaminases

Local: Pain at injection site (≥1%)

Neuromuscular & skeletal: Limb pain, muscle spasm (≥1%)

Ophthalmic: Periorbital edema

Respiratory: Abnormal breath sounds (adults: ≥1%), atelectasis (neonates, infants, children, and adolescents: ≥1%), dyspnea (adults: ≥1%), hypoxia, pleural effusion (neonates, infants, children, and adolescents: ≥1%), pulmonary edema (neonates, infants, children, and adolescents: ≥1%), stridor (adults: ≥1%), wheezing (adults: ≥1%)

Miscellaneous: Fever (neonates, infants, children, and adolescents: ≥1%)

All formulations: <1%, postmarketing, and/or case reports: Anaphylaxis, hypersensitivity reaction

How to take acetaminophen

  • Before taking acetaminophen, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about acetaminophen and a full list of the side-effects which you may experience from taking it.
  • Take acetaminophen exactly as you have been told by your physician or pharmacist, or as directed on the label of the container. Follow the instructions given in the manufacturer's packaging.
  • Acetaminophen oral liquids for infants may be available in more than one strength; always check the manufacturer's dosing instructions. Most products contain 160 mg per 5 ml. It is best to give the dose based on the weight of your child.
  • Recommended doses of acetaminophen are:
    • For adults: 500 mg-1 g every 4-6 hours up to a maximum of 4 g daily.
    • For children aged 12-16 years: 480-750 mg every 4-6 hours up to a maximum of four doses daily.
    • For children aged 11 years (72-95 lb): 480 mg (15 ml) every 4-6 hours up to a maximum of four doses daily.
    • For children aged 9-10 years (60-71 lb): 400 mg (12.5 ml) every 4-6 hours up to a maximum of four doses daily.
    • For children aged 6-8 years (48-59 lb): 320 mg (10 ml) every 4-6 hours up to a maximum of four doses daily.
    • For children aged 4-5 years (36-47 lb): 240 mg (7.5 ml) every 4-6 hours up to a maximum of four doses daily.
    • For children aged 2-3 years (24-35 lb): 160 mg (5 ml) every 4-6 hours up to a maximum of four doses daily.
    • For children aged under 2 years: consult your physician or pharmacist for the correct dose.
  • You can take a dose of acetaminophen every 4-6 hours if needed, up to four times a day. Remember to leave at least four hours between doses and do not take more than four doses of acetaminophen in any 24-hour period.
  • You can take acetaminophen before or after food.
  • Always use the measuring device (oral syringe or dropper) that comes with infant medicines.
  • Never take more than the dose recommended on the label. Taking too much acetaminophen can cause damage to your liver. If you suspect that you or someone else might have taken an overdose of acetaminophen, go to the accident and emergency department of your local hospital at once, even if you/they feel well. Take the container with you so that the physician knows what has been taken.
  • If you forget to take a dose, do not worry. Do not take two doses together to make up for a forgotten dose.

Can acetaminophen tablets cause problems?

Acetaminophen rarely causes side-effects when it is taken as recommended, but if you experience any symptoms which you think may be due to it, discuss them with your pharmacist or physician.

How to store acetaminophen

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.

Patient information

Liver warning: This product contains acetaminophen. Severe liver damage may occur if:

  • adult takes more than 12 caplets in 24 hours, which is the maximum daily amount
  • child takes more than 5 doses in 24 hours, which is the maximum daily amount
  • taken with other drugs containing acetaminophen
  • adult has 3 or more alcoholic drinks every day while using this product.

Do not use

  • with any other drug containing acetaminophen (prescription or nonprescription). If you are not sure whether a drug contains acetaminophen, ask a doctor or pharmacist.
  • if you are allergic to acetaminophen or any of the inactive ingredients in this product

Stop use and ask a doctor if

  • pain gets worse or lasts more than 10 days in adults
  • pain gets worse or lasts more than 5 days in children under 12 years
  • fever gets worse or lasts more than 3 days
  • new symptoms occur
  • redness or swelling is present

These could be signs of a serious condition.

If pregnant or breast-feeding, ask a health professional before use.

Keep out of reach of children.

Ask a doctor before use if the user has liver disease

Ask a doctor or pharmacist before use if the user is taking blood thinning drug warfarin.

Acetaminophen Drug Class

Acetaminophen is part of the drug class:

  • Anilides

Acetaminophen Interactions

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

  • anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven)
  • isoniazid (INH)
  • certain medications for seizures including carbamazepine (Tegretol), phenobarbital, and phenytoin (Dilantin)
  • medications for pain, fever, coughs, and colds
  • medications for mental illness and nausea such as chlorpromazine, thioridazine, perphenazine, and prochlorperazine (Compro, Procomp)

This is not a complete list of acetaminophen drug interactions. Ask your doctor or pharmacist for more information.

Acetaminophen Food Interactions

Medications can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of acetaminophen, there are no specific foods that you must exclude from your diet when receiving this medication.

What should I avoid while taking acetaminophen?

Ask a doctor or pharmacist before using any other cold, allergy, pain, or sleep medication. Acetaminophen (sometimes abbreviated as APAP) is contained in many combination medicines. Taking certain products together can cause you to get too much acetaminophen which can lead to a fatal overdose. Check the label to see if a medicine contains acetaminophen or APAP.

Avoid drinking alcohol. It may increase your risk of liver damage while taking acetaminophen.

Acetaminophen dosing information

Usual Adult Dose for Fever:

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:

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 Fever:

PARENTERAL:
2 to 12 years: 15 mg/kg IV or 12.5 mg/kg IV every 4 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

13 years or older; 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 Daily Dose: 75 mg/kg in 24 hours

13 years or older; 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 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:
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
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
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
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
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
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
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
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

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

RECTAL:
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
3 to 6 years: 120 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
6 to 12 years: 325 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
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 the management of moderate to severe pain with adjunctive opioid analgesics.
-For the reduction of fever.

Usual Pediatric Dose for Pain:

PARENTERAL:
2 to 12 years: 15 mg/kg IV or 12.5 mg/kg IV every 4 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

13 years or older; 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 Daily Dose: 75 mg/kg in 24 hours

13 years or older; 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 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:
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
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
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
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
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
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
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
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

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

RECTAL:
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
3 to 6 years: 120 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
6 to 12 years: 325 mg rectally every 4 to 6 hours up to a maximum of 5 doses in 24 hours
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 the management of moderate to severe pain with adjunctive opioid analgesics.
-For the reduction of fever.

In Summary

More frequently reported side effects include: fever. See below for a comprehensive list of adverse effects.

Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Rarely, may cause itchiness, constipation, nausea, vomiting, headache, insomnia, and agitation. May cause gastrointestinal side effects at high dosages.
  • The potential for liver damage exists, even at recommended dosages. The risk is increased with higher dosages, a shorter interval between doses, in people who drink three or more alcoholic drinks per day, when taken with other medications that also contain acetaminophen, and in patients with pre-existing liver disease.
  • Considered less effective for pain relief than NSAIDs but associated with a lower risk of side effects.
  • May not be suitable for some people including people who regularly consume three or more glasses of alcohol per day and those with liver disease.
  • May interact with some other medications including warfarin.

Notes: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. For a complete list of all side effects, click here.

Tips

  • May be administered without regards to food; although food may decrease any reported stomach upset.
  • Do not exceed the recommended dosage, because this may put you at risk of liver toxicity. Adults and teenagers who weigh at least 110 pounds (50kg) should not take more than 1000mg of acetaminophen in one dose or more than 4000mg in 24 hours. Children younger than 12 years should only take the dosage recommended to them on the label (this varies depending on their weight and age).
  • Always seek your doctor's advice before administering acetaminophen to children aged less than two. If you are giving pediatric acetaminophen, always use the dosing syringe provided, or another suitable properly calibrated measure. Do NOT use a kitchen teaspoon.
  • Shake liquid paracetamol before use.Chewable tablets should be properly chewed before swallowing. Hands should be dry before handling the acetaminophen disintegrating tablet, then the tablet should be placed on the tongue and allowed to fully dissolve before swallowing. The acetaminophen disintegrating granules should be dissolved in at least four ounces of water; the mixture stirred, then drunk straight away.
  • Be careful not to administer other products containing acetaminophen at the same time. Acetaminophen is often an ingredient in combination cold and flu remedies.
  • Men should not drink more than two alcoholic drinks a day and women no more than one alcoholic drink per day while taking acetaminophen.
  • Contact your doctor if symptoms worsen, you develop a skin rash, if redness or swelling occurs in the painful area, if fever lasts longer than 3 days (all ages), or for persistent pain (excluding sore throat) of longer than 10 days in adults, 5 days in children and adolescents, or 3 days for infants.
  • Contact your doctor immediately if you or your child have a sore throat that is severe, persists for longer than 2 days, or is followed by fever, rash, headache, nausea, or vomiting.
  • Seek urgent medical attention if you develop pain in your upper abdomen, dark urine, loss of appetite, yellowing of the skin or eyes or clay-colored stools.
  • Do not take acetaminophen without your doctor's advice if you are pregnant.
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