Benadryl Dosing for a 22-Pound Toddler
For a 22-pound (10 kg) toddler, give 10 mg of diphenhydramine (Benadryl) syrup as the recommended dose, using the lower end of the 1-2 mg/kg dosing range that the American Academy of Pediatrics recommends for infants and young children. 1
Dosing Calculation
- A 22-pound child weighs exactly 10 kg (22 lbs ÷ 2.2 = 10 kg)
- The American Academy of Pediatrics recommends 1-2 mg/kg per dose, with infants and young children receiving the lower end of this range (1 mg/kg) 1
- For this 10 kg toddler: 1 mg/kg × 10 kg = 10 mg per dose 1
- The maximum single dose is 50 mg regardless of weight, which is well above this calculated dose 1
Important Administration Considerations
- Use oral liquid formulations rather than tablets, as the American Academy of Pediatrics notes these are more readily absorbed for acute allergic reactions 1
- Most diphenhydramine syrups are concentrated at 12.5 mg per 5 mL, so 10 mg = 4 mL of syrup 1
Critical Safety Warnings
- Monitor closely for sedation and respiratory suppression, especially if other sedative medications are being used concurrently 1
- Be aware that diphenhydramine may cause paradoxical excitation or agitation in some pediatric patients rather than sedation 1
- If the child ingests 7.5 mg/kg or more (75 mg for this 10 kg child), immediate referral to an emergency department is warranted due to toxicity risk 2
Clinical Context Considerations
- For anaphylaxis, diphenhydramine is always second-line to epinephrine and should never be administered alone 1
- If treating acute hypersensitivity reactions or anaphylaxis, the dose can be increased to 1-2 mg/kg (10-20 mg for this child), but epinephrine must be given first 1
- Combination with ranitidine (1 mg/kg) is superior to diphenhydramine alone when managing anaphylaxis 1