Acetaminophen Dosage

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Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Fever

IV:
Adults and adolescents weighing 50 kg and over: 1000 mg every 6 hours or 650 mg every 4 hours, with a maximum single dose of 1000 mg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 4000 mg per day.
Adults and adolescents weighing under 50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours, with a maximum single dose of 15 mg/kg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 75 mg/kg per day.

Orally or Rectally:
General Dosing Guidelines: 325 to 650 mg every 4 to 6 hours or 1000 mg every 6 to 8 hours

No dose adjustment is required when converting between oral and IV acetaminophen dosing in adults and adolescents. The maximum daily dose of acetaminophen is based on all routes of administration
(i.e. intravenous, oral, and rectal) and all products containing acetaminophen.

Usual Adult Dose for Pain

IV:
Adults and adolescents weighing 50 kg and over: 1000 mg every 6 hours or 650 mg every 4 hours, with a maximum single dose of 1000 mg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 4000 mg per day.
Adults and adolescents weighing under 50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours, with a maximum single dose of 15 mg/kg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 75 mg/kg per day.

Orally or Rectally:
General Dosing Guidelines: 325 to 650 mg every 4 to 6 hours or 1000 mg every 6 to 8 hours

No dose adjustment is required when converting between oral and IV acetaminophen dosing in adults and adolescents. The maximum daily dose of acetaminophen is based on all routes of administration
(i.e. intravenous, oral, and rectal) and all products containing acetaminophen.

Usual Pediatric Dose for Fever

Preterm neonates 28 to 32 weeks:
IV loading dose: 20 mg/kg followed by 10 mg/kg/dose every 12 hours
Oral: 10 to 12 mg/kg/dose every 6 to 8 hours
Maximum oral daily dose: 40 mg/kg/day
Rectal: 20 mg/kg/dose every 12 hours
Maximum rectal daily dose: 40 mg/kg/day

Preterm neonates 32 to 37 weeks and term neonates less than 10 days:
IV loading dose: 20 mg/kg followed by 10 mg/kg/dose every 6 hours
Oral: 10 to 15 mg/kg/dose every 6 hours
Maximum daily dose: 60 mg/kg/day
Rectal: Loading dose: 30 mg/kg; then 15 mg/kg/dose every 8 hours
Maximum daily dose: 60 mg/kg/day

Term neonates greater than or equal to 10 days:
IV loading dose: 20 mg/kg followed by 10 mg/kg/dose every 6 hours
Oral: 10 to 15 mg/kg/dose every 4 to 6 hours
Maximum daily dose: 90 mg/kg/day
Rectal: Loading dose: 30 mg/kg; then 20 mg/kg/dose every 6 to 8 hours
Maximum daily dose: 90 mg/kg/day

Infants and Children:
IV: Less than 2 years: 7.5 to 15 mg/kg/dose every 6 hours
Maximum daily dose: 60 mg/kg/day
IV: 2 to 12 years: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours
Maximum single dose 15 mg/kg
Maximum total daily dose: 75 mg/kg/day not to exceed 3750 mg/day
Oral: 10 to 15 mg/kg/dose every 4 to 6 hours as needed; do not exceed 5 doses in 24 hours
Alternatively, the manufacturer lists the following recommended doses:
2.7 to 5.3 kg or 6 to 11 pounds: 0 to 3 months: 40 mg
5.4 to 8.1 kg or 12 to 17 pounds: 4 to 11 months: 80 mg
8.2 to 10.8 kg or 18 to 23 pounds: 1 to 2 years: 120 mg
10.9 to 16.3 kg or 24 to 35 pounds: 2 to 3 years: 160 mg
16.4 to 21.7 kg or 36 to 47 pounds: 4 to 5 years: 240 mg
21.8 to 27.2 kg or 48 to 59 pounds: 6 to 8 years: 320 mg
27.3 to 32.6 kg or 60 to 71 pounds: 9 to 10 years: 400 mg
32.7 to 43.2 kg or 72 to 95 pounds: 11 years: 480 mg
The manufacturer recommends the use of weight to select the dose as the preferred method. If weight is not available, then age may be used.
Rectal: 10 to 20 mg/kg/dose every 4 to 6 hours as needed (Although the perioperative use of high dose rectal acetaminophen (e.g., 25 to 45 mg/kg/dose) has been investigated in several studies, its routine use remains controversial; optimal doses and dosing frequency to ensure efficacy and safety have not yet been established; further studies are needed).

Children greater than or equal to 12 years:
IV: Less than 50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours
Maximum single dose: 750 mg/dose
Maximum total daily dose: 75 mg/kg/day (less than or equal to 3750 mg/day)
IV: Greater than or equal to 50 kg: 650 mg every 4 hours or 1000 mg every 6 hours
Maximum single dose: 1000 mg/dose
Maximum total daily dose: 4000 mg/day
Oral or Rectal: 325 to 650 mg every 4 to 6 hours or 1,000 mg 3 to 4 times daily
Maximum daily dose: 4000 mg/day

Usual Pediatric Dose for Pain

Preterm neonates 28 to 32 weeks:
IV loading dose: 20 mg/kg followed by 10 mg/kg/dose every 12 hours
Oral: 10 to 12 mg/kg/dose every 6 to 8 hours
Maximum oral daily dose: 40 mg/kg/day
Rectal: 20 mg/kg/dose every 12 hours
Maximum rectal daily dose: 40 mg/kg/day

Preterm neonates 32 to 37 weeks and term neonates less than 10 days:
IV loading dose: 20 mg/kg followed by 10 mg/kg/dose every 6 hours
Oral: 10 to 15 mg/kg/dose every 6 hours
Maximum daily dose: 60 mg/kg/day
Rectal: Loading dose: 30 mg/kg; then 15 mg/kg/dose every 8 hours
Maximum daily dose: 60 mg/kg/day

Term neonates greater than or equal to 10 days:
IV loading dose: 20 mg/kg followed by 10 mg/kg/dose every 6 hours
Oral: 10 to 15 mg/kg/dose every 4 to 6 hours
Maximum daily dose: 90 mg/kg/day
Rectal: Loading dose: 30 mg/kg; then 20 mg/kg/dose every 6 to 8 hours
Maximum daily dose: 90 mg/kg/day

Infants and Children:
IV: Less than 2 years: 7.5 to 15 mg/kg/dose every 6 hours
Maximum daily dose: 60 mg/kg/day
IV: 2 to 12 years: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours
Maximum single dose 15 mg/kg
Maximum total daily dose: 75 mg/kg/day not to exceed 3750 mg/day
Oral: 10 to 15 mg/kg/dose every 4 to 6 hours as needed; do not exceed 5 doses in 24 hours
Alternatively, the manufacturer lists the following recommended doses:
2.7 to 5.3 kg or 6 to 11 pounds: 0 to 3 months: 40 mg
5.4 to 8.1 kg or 12 to 17 pounds: 4 to 11 months: 80 mg
8.2 to 10.8 kg or 18 to 23 pounds: 1 to 2 years: 120 mg
10.9 to 16.3 kg or 24 to 35 pounds: 2 to 3 years: 160 mg
16.4 to 21.7 kg or 36 to 47 pounds: 4 to 5 years: 240 mg
21.8 to 27.2 kg or 48 to 59 pounds: 6 to 8 years: 320 mg
27.3 to 32.6 kg or 60 to 71 pounds: 9 to 10 years: 400 mg
32.7 to 43.2 kg or 72 to 95 pounds: 11 years: 480 mg
The manufacturer recommends the use of weight to select the dose as the preferred method. If weight is not available, then age may be used.
Rectal: 10 to 20 mg/kg/dose every 4 to 6 hours as needed (Although the perioperative use of high dose rectal acetaminophen (e.g., 25 to 45 mg/kg/dose) has been investigated in several studies, its routine use remains controversial; optimal doses and dosing frequency to ensure efficacy and safety have not yet been established; further studies are needed).

Children greater than or equal to 12 years:
IV: Less than 50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours
Maximum single dose: 750 mg/dose
Maximum total daily dose: 75 mg/kg/day (less than or equal to 3750 mg/day)
IV: Greater than or equal to 50 kg: 650 mg every 4 hours or 1000 mg every 6 hours
Maximum single dose: 1000 mg/dose
Maximum total daily dose: 4000 mg/day
Oral or Rectal: 325 to 650 mg every 4 to 6 hours or 1,000 mg 3 to 4 times daily
Maximum daily dose: 4000 mg/day

Renal Dose Adjustments

IV: CrCl 30 mL/min or less: Use with caution; consider decreasing daily dose and extending dosing interval.

Oral:
Children:
CrCl less than 10 mL/min: Administer every 8 hours
Adults:
CrCl 10 to 50 mL/min: Administer every 6 hours
CrCl less than 10 mL/min: Administer every 8 hours

Liver Dose Adjustments

Use with caution. Limited, low-dose therapy is usually well tolerated in hepatic disease/cirrhosis; however, cases of hepatotoxicity at daily acetaminophen dosages less than 4000 mg/day have been reported. Avoid chronic use in hepatic impairment.

Dose Adjustments

Do not exceed 4 g in a 24 hour period.

For adult and adolescent patients weighing greater than or equal to 50 kg requiring 1000 mg doses of acetaminophen, administer the dose IV over 15 minutes.

Precautions

McNeil Consumer Healthcare announced the maximum daily dose of single-ingredient Extra Strength Tylenol (R) OTC products will be lowered from 4 g/day to 3 g/day on product packages beginning in the fall of 2011. Additionally, the dosing frequency will change from 1 g every 4 to 6 hours to 1 g every 6 hours. Of note, the labeling of Regular Strength Tylenol (R) and other McNeil OTC acetaminophen-containing products is expected to have similar labeling revisions beginning sometime in 2012.

Cases of acute liver failure (some resulting in liver transplant and death) have been reported with acetaminophen. Most cases of liver injury are associated with doses greater than 4 g per day, and often involve more than one acetaminophen-containing product. The excessive intake of acetaminophen may be intentional to cause self-harm or unintentional as patients try to get more pain relief or unknowingly take other acetaminophen-containing products. Patients should be advised to check package labels for acetaminophen (or APAP) and not to use more than one product that contains acetaminophen. Patients should seek medical attention at once if more than 4 g of acetaminophen is taken per day, even if they feel well.

Patients who consume three or more alcohol containing drinks per day should be informed to consult with their physician for advice on when and how to take acetaminophen. Chronic, heavy alcohol users may be at increased risk of liver damage when taking more than recommended dosages.

Patients and adults taking care of children should be advised to consult with their doctor before continuing to use acetaminophen if symptoms of illness worsen. Although rare, there is the possibility of acetaminophen intoxication on chronic use of the drug, and the symptoms seen during the first phase of intoxication (nausea, vomiting, anorexia, malaise, and diaphoresis) may trigger the use of more doses.

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

Extended release products: Do not crush or chew.

Meltaways (R) and Quick*Melts (R): Dissolve in mouth or chew before swallowing.

No dose adjustment is required when converting between oral and IV acetaminophen dosing in adults and adolescents. The maximum daily dose of acetaminophen is based on all routes of administration
(i.e. intravenous, oral, and rectal) and all products containing acetaminophen.

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