Benadryl (Diphenhydramine) Should Not Be Used in Infants
Diphenhydramine is contraindicated in infants under 6 years of age according to FDA labeling, and should be avoided in neonates due to significant risks of respiratory depression, sedation, paradoxical agitation, and potential seizures. 1, 2
FDA-Approved Age Restrictions
- The FDA explicitly states "Do not use" for children under 6 years of age for over-the-counter diphenhydramine products 1
- This represents the clearest regulatory guidance against using this medication in the infant population
- The approved dosing begins only at age 6 years and older (10 mL or 25 mg for children 6 to under 12 years) 1
Specific Risks in Neonates and Infants
Neonates face particularly severe adverse effects including:
- Respiratory suppression and sedation 2
- Hypotension 2
- Paradoxical excitement or agitation 2
- Risk of seizures, especially with rapid IV administration 2
- Documented cases of severe toxicity and death in young children, including from topical application 3
Lack of Pediatric Emergency Guidelines
- The American Academy of Pediatrics does not include specific dosing recommendations for diphenhydramine in neonates in their pediatric emergency medication guidelines 2, 4
- While pediatric guidelines mention diphenhydramine for acute hypersensitivity reactions at 1-2 mg/kg IV/IM (maximum 50 mg), these recommendations are not specific to neonates and should not be extrapolated to this age group 2
Safer Alternatives for Allergic Reactions
For allergic reactions in infants requiring intervention:
- Epinephrine remains the first-line treatment for severe allergic reactions, with appropriate neonatal dosing of 0.01-0.03 mg/kg of 1:10,000 solution 2
- Consultation with a pediatric allergist or emergency medicine specialist is strongly recommended before administering any antihistamine to a neonate 2
- Second-generation antihistamines have better safety profiles in older children, though data in infants remain limited 4, 5
Additional Safety Concerns
Diphenhydramine carries multiple warnings even in approved age groups:
- Should not be used "to make a child sleepy" 1
- Can cause marked drowsiness and excitability, especially in children 1
- Risk of respiratory problems in patients with chronic bronchitis 1
- Documented case of severe neonatal depression from maternal ingestion before delivery 6
Toxicity Thresholds
If accidental ingestion occurs:
- Children less than 6 years of age who ingest at least 7.5 mg/kg of diphenhydramine should be referred to an emergency department 7
- Close monitoring for respiratory depression, hypotension, and neurological effects is essential if diphenhydramine must be administered in emergency situations 2
- Do not induce emesis due to potential for rapid loss of consciousness or seizures 7
Clinical Bottom Line
There is no safe or FDA-approved indication for diphenhydramine use in infants. The combination of explicit FDA contraindication, lack of neonatal-specific guidelines from major pediatric organizations, documented cases of severe toxicity, and availability of safer alternatives makes diphenhydramine an inappropriate choice for this age group. 1, 2, 3, 5