Which antihistamines are FDA‑approved for use in children, and what are the appropriate age‑specific dosing recommendations?

FDA-Approved Antihistamines in Children

Second-generation antihistamines—specifically cetirizine, desloratadine, fexofenadine, levocetirizine, and loratadine—are the FDA-approved and recommended antihistamines for children, with demonstrated safety and efficacy profiles superior to first-generation agents. 1

Critical Age-Based Safety Distinctions

Children Under 2 Years

• First-generation antihistamines (diphenhydramine, brompheniramine, chlorpheniramine) should NOT be used due to documented fatalities and serious adverse events 1
• Between 1969-2006,69 deaths were associated with these three first-generation antihistamines in children ≤6 years, with 41 deaths occurring in children under age 2 1
• Deaths resulted from overdose errors, use of multiple products simultaneously, medication errors, and accidental exposures 1

Children Under 6 Years

• OTC cough and cold products containing antihistamines should be avoided 1
• The FDA's Nonprescription Drugs and Pediatric Advisory Committees recommended against OTC cough/cold medications in this age group 1
• Antihistamine-decongestant combinations are ineffective for upper respiratory infections in young children 1

Recommended Second-Generation Antihistamines

These agents have excellent safety profiles when used appropriately in young children: 1

Available for Children Under 5 Years:

• Cetirizine - approved for infants as young as 6 months 2, 3
• Loratadine - approved for young children 3
• Desloratadine - has data in infants 4

Available for Children 6 Years and Older:

• Fexofenadine
• Levocetirizine

Key Safety Advantages of Second-Generation Agents

Why second-generation antihistamines are preferred: 1

• No sedation at recommended doses (fexofenadine, loratadine, desloratadine)
• Minimal CNS effects compared to first-generation agents
• No anticholinergic side effects
• Once-daily dosing improves adherence
• No cardiovascular toxicity (unlike older agents astemizole, terfenadine)
• Well-tolerated in long-term use

Important Sedation Distinctions:

• Non-sedating: Fexofenadine, loratadine, desloratadine 1
• May cause mild sedation: Cetirizine (13.7% vs 6.3% placebo in children ≥12 years) 1
• Intranasal azelastine: May cause somnolence (11.5% of patients) 1

Critical Pitfalls to Avoid

1. Never use multiple cough/cold products simultaneously - this was a common cause of fatal overdoses 1

2. Do not use first-generation antihistamines in children under 6 years - risks include agitated psychosis, ataxia, hallucinations, and death 1

3. Avoid first-generation agents in older children when possible due to:

   • Performance impairment without subjective awareness of drowsiness 1
   • Anticholinergic effects
   • Increased risk of accidents and falls 1

4. Do not prescribe antihistamines for common cold symptoms in young children - they are ineffective for viral upper respiratory infections 1

Clinical Application Algorithm

For allergic conditions (allergic rhinitis, urticaria, allergic conjunctivitis):

• Age 6 months to <2 years: Cetirizine or loratadine only (prescription formulations)
• Age 2-5 years: Cetirizine, loratadine, or desloratadine
• Age 6+ years: Any second-generation antihistamine (cetirizine, loratadine, desloratadine, fexofenadine, levocetirizine)

For viral upper respiratory infections:

• Age <6 years: No antihistamines recommended 1
• Age ≥6 years: Consider second-generation antihistamines only if allergic component suspected

Dosing Considerations

• Liquid formulations or oral disintegrating tablets are available for most agents, facilitating administration in young children 4
• Children with low body mass may experience increased sedation even at standard age-based doses due to higher mg/kg dosing 1
• Dose adjustments needed in renal impairment (cetirizine, levocetirizine require 50% dose reduction) 5