Hydroxyzine Dosing for a 13-kg Child
For a 13-kg child, administer hydroxyzine at 0.5-1 mg/kg per dose, which equals 6.5-13 mg per dose, with a maximum daily dose of 50 mg divided throughout the day.
Dosing Based on Indication
The appropriate hydroxyzine dose depends on the clinical indication:
For Anxiety or Sedation
- Dose: 0.5-1 mg/kg per dose
- For 13 kg child: 6.5-13 mg per dose
- Daily maximum: 50 mg total daily in divided doses 1
The FDA drug label specifies that children under 6 years should receive 50 mg daily in divided doses for anxiety and tension 1. For your 13-kg child, this translates to approximately 12.5 mg given 3-4 times daily, staying well within the 50 mg daily maximum.
For Pruritus (Allergic Conditions, Urticaria)
- Same dosing applies: 50 mg daily in divided doses for children under 6 years 1
- Practical dosing: 12.5 mg three to four times daily
For Preoperative Sedation
- Dose: 0.6 mg/kg 1
- For 13 kg child: Approximately 8 mg as a single preoperative dose
Clinical Context from Research
Research supports hydroxyzine dosing in pediatric populations:
- Studies using 0.5 mg/kg hydroxyzine combined with midazolam for dental sedation showed effective sedation with good safety profiles 2, 3
- A pharmacokinetic study demonstrated that 0.7 mg/kg doses provided effective antipruritic effects with peak levels at 2 hours and elimination half-life of 7.1 hours 4
- Higher doses (3.7 mg/kg) have been used in dental sedation protocols, though this exceeds typical recommendations 5, 6
Important Safety Considerations
Monitor for these adverse effects:
- Sedation (most common)
- Paradoxical excitement or agitation
- Dry mouth
- Respiratory depression (especially when combined with other sedatives)
Caution: The 2008 Pediatrics guidelines note that hydroxyzine may cause sedation and respiratory suppression, particularly when used with other sedative agents 7. While these guidelines discuss IV/IM dosing for acute hypersensitivity reactions (1-2 mg/kg), oral dosing follows different parameters as outlined in the FDA label.