Benadryl Dosage Calculator for Children

The standard dose is 1 to 1.25 mg/kg per dose, given every 6 to 8 hours. For a 10 kg child: 12.5 mg (5 mL). For a 20 kg child: 25 mg (10 mL). For a 30 kg child: 37.5 mg (15 mL). Maximum single dose is 50 mg regardless of weight.

Benadryl is generally not recommended for children under 2 years old without explicit guidance from a pediatrician. The risk of overdose is higher in infants and toddlers. If your doctor approves it, use the infant concentration (6.25 mg/5 mL) with a precise dosing syringe.

Every 6 to 8 hours as needed, with a maximum of 4 doses in 24 hours. Do not give more frequently than every 6 hours. If symptoms persist beyond 7 days or worsen, consult your pediatrician.

Yes, drowsiness is the most common side effect, affecting over 50% of children. This is because diphenhydramine is a first-generation antihistamine that crosses the blood-brain barrier. For daily allergy management, second-generation antihistamines like cetirizine (Zyrtec) or loratadine (Claritin) cause less drowsiness.

Maximum single dose: 50 mg (regardless of weight). Maximum daily dose: 5 mg/kg per day or 300 mg total, whichever is less. For a 20 kg child, max daily is 100 mg (4 doses of 25 mg). For a 40 kg child, max daily is 200 mg (4 doses of 50 mg).

No. The American Academy of Pediatrics advises against using Benadryl or any antihistamine as a sleep aid for children. While drowsiness is a common side effect, using it for sleep can lead to dependency, paradoxical excitability in some children, and masks underlying sleep issues that should be addressed differently.