Paracetamol Dosage Calculator by Weight

Pediatric Paracetamol Dosing

Paracetamol is considered a drug that can be used for pain and fever relief in children and infants, without causing drowsiness, frequent or serious side effects. Paracetamol requires doctor’s dosing advice for administration to infants younger than 3 months and with a weight of 5 kg (11 lbs) or lower.

The paracetamol dose, as is the case with most other pediatric dosings, should be based on the child’s actual body weight, not their age, without exceeding the adult dose, nor take more than four doses, at 4 to 6 hours apart.

The oral dose of paracetamol for infants and children is: 15 mg/kg per dose, to a maximum of 1 g per dose, every four to six hours (to a maximum of four doses per day), with a maximum of 60 mg/kg daily, without exceeding 4 g daily.

Examples of paracetamol formulas include:

• Infant Syrup (120 mg/5 mL)
• Six plus syrup (250 mg/5 mL)
• Tablets (500 mg)

A loading dose of 30 mg/kg (up to 1.5 g) may be given provided there has been no paracetamol administered within the preceding 12 hours.

It was found that due to the narrow therapeutic index of paracetamol, children under five years who are acutely unwell are particularly vulnerable to paracetamol toxicity and at increased risk of overdose.

Caution must be exerted when the weight-based dosing is applied to children weighing over 65 kg (143 lbs) so that daily adult paracetamol dose (4 g/day) is not exceeded.

Caution must also be exerted when administering paracetamol to children who are severely under-weight or malnourished, due to greater susceptibility to paracetamol toxicity (because of reduced levels of the detoxifying glutathione enzyme). Reduced 10 mg/kg doses or longer periods between dosing may be adopted in such cases.

It’s recommended to give the lowest dose that’s effective for the shortest period of time. Safe dosing guidelines are crucial in avoiding overdosing or poisonous ingestion.

The three most common errors in administering paracetamol include:

• Exceeding recommended doses;
• Dosing more frequent than at 4-6hours, up to 4 times a day;
• Prolonged dosing (several days).

References

Goldstein LH, Berlin M, Berkovitch M, Kozer E. Effectiveness of oral vs rectal acetaminophen: a meta-analysis. Arch Pediatr Adolesc Med. 2008; 162(11):1042-1046.

Pierce CA, Voss B. Efficacy and safety of ibuprofen and acetaminophen in children and adults: a meta-analysis and qualitative review. Ann Pharmacother. 2010; 44(3):489-506.

Bilenko N, Tessler H, Okbe R, Press J, Gorodischer R. Determinants of antipyretic misuse in children up to 5 years of age: a cross-sectional study. Clin Ther. 2006; 28(5):783-93.