What is the recommended dose of brompheniramine (antihistamine) maleate for a 3-year-old?

Brompheniramine Maleate Dosing for a 3-Year-Old

For a 3-year-old child, administer brompheniramine maleate 2.5 mL (½ teaspoonful) every 4 hours, not exceeding 6 doses in 24 hours. 1

FDA-Approved Dosing

The FDA-approved dosing for brompheniramine maleate in children aged 2 to under 6 years is straightforward and weight-independent within this age bracket 1:

• Dose: 2.5 mL (½ teaspoonful) every 4 hours 1
• Maximum frequency: Do not exceed 6 doses in 24 hours 1
• This translates to approximately 1 mg per dose (assuming standard 2 mg/5 mL concentration) 1

Pharmacokinetic Considerations in Young Children

The dosing recommendation is supported by pharmacokinetic data showing that age-appropriate weight-based dosing achieves similar drug exposure across pediatric age groups 2:

• Peak concentrations (Cmax) are similar across all pediatric age groups when using age/weight-based dosing 2
• Time to peak concentration occurs earlier in younger children (2-5 years) compared to older children 2
• Terminal elimination half-life is approximately 15 hours in children, supporting dosing intervals of 4-6 hours 3, 2
• Duration of antihistamine effect extends 24-30 hours after a single dose, with maximum wheal suppression occurring at 12 hours 3

Critical Safety Warnings

Sedation is the most common adverse effect and appears more prevalent in the 2-5 year age group 2:

• Monitor closely for excessive sedation, particularly after the first dose 2
• Ensure caregivers understand not to exceed the maximum daily dose of 6 administrations 1
• Be aware that a subset of asthmatic children may experience bronchospasm with brompheniramine; premedication with bronchodilators may be necessary if the child has asthma 4

Important Clinical Caveats

The FDA and pediatric advisory committees have raised significant concerns about OTC cough and cold medications in young children 5:

• Between 1969-2006, there were 9 pediatric fatalities associated with brompheniramine, with drug overdose and medication errors being common contributing factors 5
• Efficacy of antihistamine-decongestant combinations has not been established for upper respiratory infections in children under 6 years 5
• The 2007 FDA advisory committees recommended against using OTC cough and cold medications in children under 6 years, though the FDA has not formally implemented this recommendation 5

Therefore, brompheniramine should only be used for clear allergic indications (allergic rhinitis, urticaria) rather than common cold symptoms in this age group 5. Ensure the diagnosis is allergic rhinitis or another histamine-mediated condition, not a viral upper respiratory infection 5.

Practical Administration Tips

• Administer with or without food; food does not significantly affect absorption 3
• Use an accurate measuring device (oral syringe or dosing cup) rather than household spoons 1
• Onset of action occurs within 30 minutes, with peak effect at 3-6 hours 3
• If sedation is problematic, consider administering doses later in the day or at bedtime 2