Desloratadine Dosing in Pediatric Patients
Desloratadine dosing in children is strictly age-based: 1 mg once daily for infants 6-11 months, 1.25 mg once daily for children 1-5 years, and 2.5 mg once daily for children 6-11 years, with all doses given as syrup formulation. 1
Age-Specific Dosing Regimen
Infants 6-11 Months
- Dose: 1 mg (2 mL of 0.5 mg/mL syrup) once daily 1
- This dose achieves systemic exposure comparable to the adult 5 mg dose based on population pharmacokinetic modeling 1
Children 1-5 Years
- Dose: 1.25 mg (2.5 mL of 0.5 mg/mL syrup) once daily 2, 3
- Pharmacokinetic studies demonstrate median AUC of 38.8 ng/mL·h, similar to adult exposure with 5 mg dosing 3
- Peak plasma concentration (Cmax) occurs at median 2.0 hours post-dose 3
Children 6-11 Years
- Dose: 2.5 mg (5 mL of 0.5 mg/mL syrup) once daily 2, 3
- Median AUC of 38.2 ng/mL·h matches adult pharmacokinetic profile 3
- Harmonic mean half-life is 15.8 hours, supporting once-daily dosing 3
Pharmacokinetic Rationale
The apparent clearance (CL/F) of desloratadine increases with age: 27.8 L/h in infants 6-11 months, 35.5 L/h in children 1-2 years, compared to 137 L/h in adults 1. This age-dependent clearance necessitates the lower pediatric doses to achieve equivalent drug exposure. The dosing strategy ensures that children achieve similar systemic exposure to adults receiving the established efficacious 5 mg dose 1.
Administration Guidelines
- Formulation: Use desloratadine syrup (0.5 mg/mL concentration) for all pediatric patients under 12 years 2, 3
- Timing: Once-daily administration; food does not affect absorption 4
- Steady state: Achieved after approximately 5 doses with consistent once-daily dosing 4
Safety Profile
Desloratadine demonstrates excellent tolerability across all pediatric age groups 2. In controlled trials of children 2-11 years:
- Adverse event incidence in the 2-5 year age group: 7/55 (desloratadine) vs 6/56 (placebo) 2
- Adverse event incidence in the 6-11 year age group: 1/60 (desloratadine) vs 6/60 (placebo) 2
- No severe or serious adverse events occurred in any pediatric study 2
- No clinically significant ECG changes, including QTc prolongation (all subjects maintained QTc <440 ms) 2
- No sedation or psychomotor impairment at approved doses 4, 5
Critical Prescribing Considerations
Do not use weight-based dosing for desloratadine—unlike many pediatric medications, desloratadine dosing is determined solely by age brackets, not by weight in kg 2, 3, 1. This is a common prescribing error to avoid.
Do not adjust dose for food intake—desloratadine absorption is unaffected by meals, allowing flexible administration timing 4.
No dose adjustment needed for drug interactions—desloratadine lacks clinically relevant interactions with cytochrome P450 inhibitors (ketoconazole, erythromycin) or alcohol 4.