What is the recommended dosage of Cetirizine (antihistamine) syrup for a 1-year-old child?

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Cetirizine Syrup Dosage for a 1-Year-Old Child

For a 1-year-old child, the recommended dosage of cetirizine syrup is 2.5 mg (½ teaspoon of 5 mg/5 mL syrup) once daily. 1

Dosing Guidelines for Cetirizine in Young Children

  • Cetirizine is available as oral drops for precise dosing in infants 6-11 months, making it suitable for administration to young children 1
  • For infants aged 6-11 months, safety studies have shown that cetirizine at a dose of 0.25 mg/kg twice daily is well-tolerated 2
  • The mean daily dose used in safety studies for infants was approximately 4.5 mg per day, divided into two doses 2
  • For a typical 1-year-old child, this translates to approximately 2.5 mg once daily 1

Safety Profile in Young Children

  • Cetirizine has been extensively studied in young children and has demonstrated an excellent safety profile 3
  • In the largest and longest randomized, double-blind, placebo-controlled safety investigation of any H1-antagonist in children, cetirizine showed no significant adverse effects compared to placebo 3
  • No prolongation in the QT interval was observed in cetirizine-treated infants compared to placebo in clinical studies 2
  • The most commonly reported side effects in children are similar to placebo and include headache, pharyngitis, and abdominal pain 4

Administration Considerations

  • Cetirizine can be administered in the evening if drowsiness occurs 1
  • The medication begins working within 20 minutes of administration and effects persist for 24 hours, allowing for once-daily dosing 5
  • No tolerance to the antihistamine effect develops even after 1 month of daily treatment 5

Potential Side Effects

  • Cetirizine is generally well-tolerated in children with a safety profile comparable to placebo 3
  • Mild drowsiness may occur in approximately 13.7% of pediatric patients 1
  • Unlike first-generation antihistamines, cetirizine has minimal anticholinergic effects and limited CNS penetration 5

Clinical Efficacy

  • Cetirizine is effective for treating allergic conditions including seasonal allergic rhinitis, perennial allergic rhinitis, and chronic urticaria 5
  • It has anti-inflammatory properties in addition to its antihistamine effects, which may provide additional benefits 5
  • The medication has been shown to significantly reduce total symptom severity scores compared to placebo in children with allergic conditions 4

Remember to measure the dose accurately using the provided measuring device, and consult with your pediatrician before starting any medication in a young child.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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