Diclofenac Dosing for a 3-Year-Old Weighing 22 kg
For a 3-year-old child weighing 22 kg, diclofenac should be dosed at 1 mg/kg per dose, administered every 8 hours, which equals 22 mg per dose (66 mg total daily dose), not to exceed a maximum of 75-100 mg per day.
Weight-Based Dosing Calculation
- The standard pediatric dosing for diclofenac is 1 mg/kg per dose, administered every 8 hours (three times daily) 1
- For this 22 kg child: 1 mg/kg × 22 kg = 22 mg per dose
- Total daily dose: 22 mg × 3 doses = 66 mg/day
- This falls well within the safe maximum daily dose range of 75-100 mg/day for children 1
Route of Administration
- Oral administration is the most commonly used route (81% of pediatric anesthesiologists prefer this) and should be the first-line choice 1
- Rectal administration (80% usage) is an alternative if oral route is not feasible 1
- The medication should ideally be given with meals to reduce potential gastrointestinal side effects 2, 3
Age and Licensing Considerations
- Diclofenac is licensed for use in children over 1 year of age, making it appropriate for this 3-year-old patient 1
- Despite limited pharmacokinetic and pharmacodynamic data in young children, diclofenac is commonly prescribed by pediatric specialists in this age group 1
Dosing Interval and Duration
- The 8-hourly dosing schedule (every 8 hours) is employed by 53% of pediatric anesthesiologists and represents standard practice 1
- For acute pain conditions, treatment duration should not exceed 5 days without medical reassessment 3
- The drug has a short elimination half-life of 1-2 hours in plasma but persists longer in synovial fluid, supporting the 8-hour dosing interval 2, 3
Important Safety Considerations
- Maximum daily dose: Do not exceed 75-100 mg/day in pediatric patients to minimize risk of toxicity 1
- Monitor for gastrointestinal adverse effects, though these are generally less frequent than with aspirin or indomethacin 2
- Ensure adequate hydration and avoid use in patients with renal impairment, as conjugate accumulation can occur 4
- The drug is extensively protein-bound and metabolized hepatically, so caution is warranted in hepatic dysfunction 4
Clinical Pitfalls to Avoid
- Do not underdose: Using less than 1 mg/kg per dose may result in inadequate analgesia 1
- Do not exceed maximum daily limits: Even though the per-dose calculation is weight-based, the total daily dose should not exceed 75-100 mg/day 1
- Avoid prolonged use: OTC treatment duration should be limited to 5 days for pain to prevent adverse effects 3
- Do not combine with other NSAIDs: This increases risk of gastrointestinal and renal toxicity without improving efficacy 4