What are the risks of long-term use of cetirizine (antihistamine) in babies?

Long-Term Cetirizine Use in Babies: Safety and Recommendations

Cetirizine is safe and well-tolerated for long-term use in babies, with an excellent safety profile demonstrated in prospective studies lasting up to 18 months in infants as young as 6 months of age. 1, 2, 3

Evidence for Safety in Infants

Established Safety Profile

• Second-generation antihistamines like cetirizine have been shown to be well-tolerated with very good safety profiles when used in young children 4, 1
• The largest and longest randomized, double-blind, placebo-controlled safety study (ETAC trial) followed 817 infants aged 12-24 months for 18 months on continuous cetirizine therapy, confirming excellent safety 3
• A prospective study in infants 6-11 months of age demonstrated that cetirizine at 0.25 mg/kg twice daily was as safe as placebo, with no differences in adverse events between groups 2

Key Safety Findings from Long-Term Studies

• No cardiac effects: No prolongation of QTc interval was observed in cetirizine-treated infants compared to placebo 2, 3
• No developmental concerns: No adverse effects on growth, behavior, cognitive function, or achievement of psychomotor milestones were documented 5, 3
• Favorable adverse event profile: Drop-outs and serious events were actually less common (though not statistically significant) in cetirizine-treated children compared to placebo 3
• Most reported symptoms were attributed to intercurrent infections or age-related concerns rather than medication effects 3

Critical Distinction from Dangerous OTC Medications

Why Cetirizine is Different

• Between 1969-2006, there were 69 fatalities associated with first-generation antihistamines (diphenhydramine, brompheniramine, chlorpheniramine) in children, with 41 deaths in children under 2 years 1, 6
• The FDA advisory committees recommended against OTC cough/cold medications in children under 6 years specifically due to these first-generation antihistamine risks 4, 6
• Second-generation antihistamines like cetirizine have demonstrated superior safety compared to first-generation antihistamines and OTC cough/cold medications 1

Potential Benefits of Long-Term Use

Beyond Symptom Control

• Long-term cetirizine treatment (18 months) demonstrated a corticosteroid-sparing effect in infants with atopic dermatitis, significantly reducing the duration of moderate-to-potent topical corticosteroid use 7
• Continuous cetirizine treatment for 3 years may reduce the development of new sensitizations in monosensitized children 8
• Cetirizine reduced the relative risk of developing asthma in infants with atopic dermatitis sensitized to grass pollen or house dust mite allergens 5

Important Caveats and Monitoring

Sedation Considerations

• Cetirizine may cause mild sedation at recommended doses (13.7% vs 6.3% placebo in older patients), though this effect is dose-related and generally milder than first-generation antihistamines 1
• Interestingly, in the infant study, there was a trend toward fewer sleep-related disturbances in the cetirizine group compared to placebo 2

Renal Function Precautions

• Halve the dose in moderate renal impairment (creatinine clearance 10-20 mL/min) 9, 1
• Avoid use in severe renal impairment (creatinine clearance <10 mL/min) 9, 1

Practical Dosing

• The established safe dose in infants is 0.25 mg/kg twice daily (mean daily dose approximately 4.5 mg) 2, 7, 3
• Cetirizine is approved for use in children from 6 months of age 9
• Cetirizine has the shortest time to maximum concentration among antihistamines, providing rapid symptom relief 1

When Long-Term Use is Appropriate

• Persistent allergic rhinitis with significant symptoms 4
• Atopic dermatitis requiring frequent topical corticosteroid use (cetirizine may reduce steroid requirements) 7
• Chronic urticaria 5
• Prevention of new sensitizations in monosensitized allergic children 8