Benadryl (Diphenhydramine) Should NOT Be Used in Infants
Diphenhydramine is contraindicated in infants and children under 6 years of age for routine use, and the FDA explicitly states "Do not use" for children under 6 years. 1
Critical Safety Concerns
The evidence strongly advises against diphenhydramine use in this age group:
Between 1969 and 2006, there were 69 deaths associated with antihistamines in children under 6 years, with diphenhydramine responsible for 33 of these deaths. 2 Notably, 41 of these deaths occurred in children under 2 years of age. 2
The FDA and pediatric advisory committees explicitly recommend against using over-the-counter cough and cold medications, including first-generation antihistamines like diphenhydramine, in children below 6 years of age. 2
The American Academy of Pediatrics does not include specific dosing recommendations for diphenhydramine in neonates in their pediatric emergency medication guidelines. 3
Serious Adverse Effects in Infants
When diphenhydramine is used in neonates and infants, it can cause:
- Significant sedation and respiratory suppression 3
- Hypotension 3
- Paradoxical excitement or agitation 3
- Risk of seizures with rapid IV administration 4
Emergency Situations Only
If diphenhydramine must be used in a life-threatening emergency (such as severe anaphylaxis), the dose is 1-2 mg/kg IV/IM (maximum 50 mg), but this should only occur under direct medical supervision with close monitoring. 3, 4
However, critical caveats apply:
- Epinephrine remains the first-line treatment for anaphylaxis, with appropriate neonatal dosing of 0.01-0.03 mg/kg of 1:10,000 solution. 3
- Diphenhydramine should never be administered alone and is always second-line to epinephrine. 4
- For infants and young children requiring antihistamine therapy under medical supervision, use the lower end of the dosing range (1 mg/kg). 4
- Avoid rapid IV administration which may precipitate seizures. 3
- Consultation with a pediatric allergist or emergency medicine specialist is strongly recommended before administering any antihistamine to a neonate. 3
Recommended Alternatives
For allergic symptoms in infants requiring treatment, second-generation antihistamines (cetirizine, loratadine, desloratadine, fexofenadine, levocetirizine) are strongly preferred due to their superior safety profile and lack of sedating effects. 2
- Cetirizine can be dosed at 2.5 mg once or twice daily for children aged 2-5 years. 2
- These agents have very low rates of serious adverse events in young children. 2
Clinical Approach for Infants with Allergic Symptoms
Rather than pharmacotherapy in a 2-month-old infant, focus on identifying and avoiding triggers, with immediate referral to a pediatric allergist if symptoms are severe enough to warrant treatment. 2