Diclofenac Dosing Recommendations for Children
The recommended dose of diclofenac for children aged 1-12 years is 0.5 mg/kg for rectal administration, 1 mg/kg for oral administration, and 0.3 mg/kg for intravenous administration, given 3 times daily. 1
Age-Specific Dosing Guidelines
Children 1-12 years:
- Oral route: 1 mg/kg/dose, 3 times daily (maximum 50 mg per dose) 1
- Rectal route: 0.5 mg/kg/dose, 3 times daily 1
- Intravenous route: 0.3 mg/kg/dose, 3 times daily 1
Children under 1 year:
- Not recommended due to insufficient pharmacokinetic and pharmacodynamic data 2
- Diclofenac is not licensed for use in children under 1 year of age 2
Maximum Daily Doses
- Total daily dose should not exceed 3 mg/kg/day when given orally
- Maximum daily dose: 150 mg per day for all routes of administration
Clinical Considerations
Efficacy
- Diclofenac has been proven effective for perioperative acute pain in children 3
- It provides opiate-sparing effects, reducing the need for post-operative rescue analgesia (NNT 3.6) 3
- Patients receiving diclofenac experience less nausea and vomiting compared to non-NSAID analgesics 3
Safety Profile
- Serious adverse reactions occur in fewer than 0.24% of children treated for acute pain 3
- The types of serious adverse reactions in children are similar to those in adults 3
- No evidence of increased risk of bleeding requiring surgical intervention when used perioperatively 3
Administration Timing
- Administer with food to minimize gastrointestinal side effects
- For post-operative pain, begin administration as soon as oral intake is tolerated
- Regular dosing provides better symptom control than as-needed dosing for acute pain
Contraindications and Precautions
- Avoid in children with:
- Known hypersensitivity to NSAIDs
- Active gastrointestinal bleeding
- Severe renal impairment
- Concurrent use with other NSAIDs
Pharmacokinetics
- Diclofenac has a rapid and complete oral absorption 4
- Extensively binds to plasma albumin 4
- Elimination occurs following biotransformation to glucoroconjugated and sulphate metabolites 4
- Mean terminal half-life is 1-2 hours, allowing for a 4-6 hour duration of activity 5
Common Pitfalls to Avoid
- Underdosing: Ensure proper weight-based dosing to achieve therapeutic effect
- Exceeding maximum daily dose: Stay within the recommended total daily dose of 3 mg/kg/day
- Inappropriate use in very young infants: Avoid use in children under 1 year due to limited safety data
- Administering on empty stomach: Always give with food to reduce GI side effects
- Prolonged use without monitoring: Limit duration of treatment to minimize risk of adverse effects
The pharmacokinetic meta-analysis by 1 provides the most recent and highest quality evidence for diclofenac dosing in children, and these recommendations are designed to achieve plasma concentrations equivalent to those seen with effective adult dosing.