Avil (Pheniramine) Dosing for an 11-Year-Old Child
For an 11-year-old child, pheniramine (Avil) should be dosed at 0.315% ophthalmic solution (1-2 drops in affected eye up to 4 times daily) if used for eye allergies, as this is the only FDA-approved formulation with specific pediatric dosing guidance available in the evidence. 1
Critical Context and Limitations
The evidence provided does not contain specific dosing information for oral pheniramine tablets (Tab Avil) in children. The only pheniramine dosing guidance available is for the ophthalmic formulation:
Available FDA-Approved Dosing 1
- Children ≥6 years: 1-2 drops of pheniramine maleate 0.315% ophthalmic solution in affected eye(s) up to 4 times daily
- Children <6 years: Requires physician consultation before use
Important Safety Warnings 1
- Accidental oral ingestion in infants and children may lead to coma and marked reduction in body temperature - this is a critical safety concern that must be emphasized
- The ophthalmic formulation should not be used if the child is sensitive to any ingredient
- Discontinue use if eye pain, vision changes, or worsening redness occurs
Clinical Approach When Oral Formulation is Intended
If oral pheniramine tablets are specifically needed (which appears to be the intent of "Tab Avil"), the following approach should be taken:
Weight-Based Dosing Principles 2, 3
- For children >6 months of age: Most medications should be normalized to body surface area (BSA) rather than simple weight-based calculations
- An 11-year-old child (typically 30-40 kg) would generally require adult-proportioned dosing adjusted for BSA
Practical Recommendation
- Consult the specific product labeling for oral pheniramine tablets, as dosing varies by formulation and indication
- General antihistamine principles suggest children ≥10 years often receive adult dosing or near-adult dosing for first-generation antihistamines
- Common pitfall: Do not exceed maximum recommended daily doses, as antihistamines can cause significant CNS effects in children 1
Key Safety Considerations
- Monitor for excessive sedation, as first-generation antihistamines like pheniramine have significant CNS penetration 1
- Avoid use with other sedating medications without appropriate medical supervision
- Ensure proper hydration, as antihistamines can cause anticholinergic effects including dry mouth
- Do not use in children with narrow-angle glaucoma, enlarged prostate (adolescents), or urinary retention 1