Cetirizine Dosing for a 28 kg Child
For a 28 kg child, the appropriate dose of cetirizine is 5 mg once daily.
Dosage Determination
Cetirizine dosing for children is weight-based, with specific recommendations for different weight categories:
- For children weighing 15-23 kg: 2.5-5 mg once daily
- For children weighing 23-40 kg: 5 mg once daily
- For children weighing >40 kg: 10 mg once daily
At 28 kg, this child falls within the 23-40 kg weight category, making 5 mg once daily the appropriate dose.
Administration Considerations
- Cetirizine is available in multiple formulations:
- Oral solution (5 mg/5 mL)
- Chewable tablets (5 mg, 10 mg)
- Regular tablets (5 mg, 10 mg)
- Can be administered with or without food
- Best administered at the same time each day for consistent effect
- For allergic rhinitis, administering in the evening may be beneficial if symptoms are worse at night
Efficacy and Evidence
Clinical studies support the efficacy of cetirizine at this dosage:
- A randomized, double-blind study showed that cetirizine 5 mg once daily was effective for treating perennial allergic rhinitis in children 6-12 years old 1
- Another study demonstrated that cetirizine at 0.2 mg/kg (approximately 5-6 mg for a 28 kg child) was effective in controlling symptoms of allergic rhinitis in children 2-6 years old 2
Side Effect Profile
The most common side effects to monitor for include:
- Mild sedation (occurs less frequently than with first-generation antihistamines but more than with some other second-generation antihistamines) 3
- Dry mouth
- Headache
- Rarely, abdominal discomfort
Important to note that cetirizine may cause mild drowsiness in some children, which could potentially affect school performance 3. However, it generally causes less sedation than first-generation antihistamines.
Clinical Pearls
- Cetirizine has a rapid onset of action (within 1 hour) and long duration (24 hours), making once-daily dosing appropriate
- If the child experiences excessive sedation with cetirizine, consider switching to a less sedating antihistamine like loratadine or fexofenadine
- For severe allergic reactions, cetirizine should not replace epinephrine as first-line therapy
- Cetirizine should be discontinued 3-7 days before allergy testing to avoid interference with results 4
This dosing recommendation aligns with established pediatric dosing guidelines and provides an effective balance between symptom control and minimizing side effects for a child weighing 28 kg.