What is the recommended paracetamol dosage in milligrams per kilogram for a child, the maximum daily dose, age restrictions (avoid neonates younger than two months), precautions for liver disease or concurrent hepatotoxic medications, and the alternative ibuprofen dosing regimen?

Paracetamol (Acetaminophen) Dosing in Children

The recommended paracetamol dose for children is 15 mg/kg per dose given every 4-6 hours, with a maximum daily dose of 60 mg/kg/day, and should not be used in neonates younger than 2 months without specific guidance. 1

Standard Dosing Regimen

Per-Dose Administration:

• 15 mg/kg per dose is the optimal therapeutic dose for both fever and pain management 1, 2
• Administer every 4-6 hours as needed 1
• Maximum of 5 doses in 24 hours 1

Maximum Daily Limits:

• 60 mg/kg/day total - never exceed this threshold 1, 2, 3
• This maximum applies regardless of number of doses given 1

Age-Specific Restrictions and Dosing

Neonates and Young Infants:

• Avoid use in neonates under 2 months unless specifically indicated, as there are no established dosing guidelines for this age group 4
• For infants under 3 months when treatment is necessary: 15 mg/kg per dose if weight is less than 10 kg 1
• For infants 1-3 months: 60-65 mg/kg/day has been suggested in literature, though pharmacokinetic data may support higher doses 4

Children 4 months and older:

• Standard 15 mg/kg per dose applies 1, 2
• Maximum 60 mg/kg/day 1

Critical Safety Considerations

Hepatotoxicity Risk:

• Single ingestions exceeding 10 times the recommended dose are potentially hepatotoxic 5
• Chronic overdosing at >140 mg/kg/day for several consecutive days carries risk of serious liver toxicity and potential liver failure 5
• Children with pre-existing liver disease should not receive paracetamol 3
• Exercise extreme caution with concurrent hepatotoxic medications 3

Dosing Errors to Avoid:

• Many older dosing schedules recommend inadequate amounts (≤10 mg/kg), which are subtherapeutic 2, 6
• Prescriptions exceeding 95 mg/kg/day have been documented in 17% of cases in hospital audits, though most were not administered due to nursing/pharmacy oversight 4
• Weight-based dosing is more accurate than age-based dosing for preventing under- or overdosing 6

Route of Administration

Oral (Preferred):

• Oral syrup formulation is absorbed more rapidly and provides more consistent response than rectal suppositories 1
• Effervescent tablets provide even faster absorption and onset of action compared to conventional tablets 3

Rectal (Use Cautiously):

• Rectal administration has slow and irregular absorption 3
• The American Academy of Pediatrics recommends rectal acetaminophen be used cautiously because of erratic absorption 1
• Some children may receive inadequate analgesia while others risk accumulation with repeated dosing 1
• Consider rectal route only for children actively vomiting or in perioperative situations where oral intake is restricted 1

Alternative: Ibuprofen Dosing

Standard Ibuprofen Regimen:

• 10 mg/kg per dose given every 6-8 hours 1
• Not recommended for infants under 6 months 1
• Available oral or rectal routes 1

Alternating Paracetamol and Ibuprofen:

• Give paracetamol every 4-6 hours and ibuprofen every 6-8 hours 1
• Stagger timing so medications are given every 3-4 hours if both are needed 1
• This approach can be used for refractory fever or pain, though paracetamol alone is first-line 1

Comparative Efficacy

Paracetamol vs NSAIDs:

• At 15 mg/kg dosing, paracetamol is significantly more effective than placebo and at least as effective as NSAIDs (ibuprofen, ketoprofen) 2
• Older studies using subtherapeutic doses of ≤10 mg/kg showed paracetamol was less effective than NSAIDs, but this reflects inadequate dosing rather than true drug efficacy 2
• When used at repetitive doses for consecutive days, paracetamol shows lower risk of adverse events compared to NSAIDs 2
• Unlike NSAIDs, paracetamol is indicated for use in children of all ages (though caution in neonates <2 months) 2

Special Clinical Situations

Febrile Seizure History:

• Paracetamol 15 mg/kg can be given prophylactically every 4 hours for 24 hours to reduce fever risk, though it does not prevent febrile seizures themselves 1

Post-Vaccination Fever:

• Can be given at time of vaccination and every 4 hours for 24 hours for fever prevention 1

Renal Insufficiency:

• Paracetamol is the non-opioid analgesic of choice in patients with chronic renal insufficiency 3
• Usually no dosage reduction necessary despite reduced clearance 3