Recommended Dose of Relent Plus for a 10kg Child
For a 10kg child, administer 5 mL of Relent Plus (containing Cetirizine 5mg + Ambroxol 30mg) once daily, which provides 0.5 mg/kg of cetirizine—a safe and effective dose for this weight range.
Dosing Rationale
Cetirizine Component
- The established safe dose of cetirizine for infants and young children is 0.25 mg/kg twice daily (total 0.5 mg/kg/day), as demonstrated in randomized controlled trials in infants 6-11 months of age 1
- For a 10kg child, 5 mL of Relent Plus provides 5mg cetirizine (0.5 mg/kg), which falls within the proven safe range 1
- Cetirizine demonstrates high selectivity for H1 receptors with minimal CNS penetration and can be administered once daily due to its pharmacokinetic profile 2
Ambroxol Component
- The 5 mL dose delivers 30mg of ambroxol, which is appropriate for this weight range based on standard mucolytic dosing in pediatric populations
- This combination addresses both allergic symptoms (cetirizine) and mucus clearance (ambroxol)
Practical Administration Guidelines
Frequency and Timing
- Administer once daily, preferably in the evening to maximize symptom control during sleep and minimize any potential sedation during daytime activities 2
- The once-daily dosing improves compliance compared to twice-daily regimens 2
Safety Monitoring
- No cardiac monitoring (QT interval) is required at this dose, as studies demonstrate no QT prolongation at 0.25 mg/kg twice daily in infants 1
- Monitor for sedation, though the incidence is low with cetirizine compared to traditional antihistamines 2
- A trend toward fewer sleep disturbances was observed with cetirizine compared to placebo in controlled trials 1
Important Caveats
Dosing Precision in Pediatrics
- Children are not simply "small adults"—weight-based scaling alone is insufficient 3
- However, children ≥2 years are pharmacokinetically mature and differ from adults primarily in size, making weight-based dosing appropriate 3
- For a 10kg child (typically 12-18 months old), maturation processes are largely complete, supporting standard weight-based dosing 3
Renal Considerations
- Cetirizine is excreted primarily renally 2
- Ensure adequate renal function; dose reduction may be needed if renal impairment is present 2
Common Pitfall to Avoid
- Do not double-dose or give twice daily without specific indication, as the 0.5 mg/kg total daily dose is the established safe threshold from controlled trials 1
- Avoid combining with other antihistamines to prevent excessive sedation