Last updated: March 2, 2026 by Maria Gonzalez

Benadryl (Diphenhydramine) Dosage Guide

Formula

Children (2+): 1.25 mg/kg per dose (max 50mg);
Adults: 25-50mg per dose;
Every 4-6 hours;
Max 300mg/day

Benadryl (diphenhydramine) is an antihistamine used to treat allergies, itching, hives, and cold symptoms. It can also be used as a short-term sleep aid due to its sedating effects.

Disclaimer: This calculator provides general guidelines only. Benadryl should not be given to children under 2 without a doctor's approval. Always consult a healthcare provider.

Common use cases:

  • Allergy symptom relief dosing
  • Pediatric dosing by weight
  • Understanding safe maximum limits

Frequently Asked Questions

MG

Maria Gonzalez

Registered Dietitian, RD, MPH

Maria is a Registered Dietitian with a Master's in Public Health. She focuses on evidence-based nutrition assessment tools including BMI, calorie calculations, and body composition analysis.

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