Benadryl Dosage Calculator for Dogs

Calculate the safe and accurate Benadryl (diphenhydramine) dosage for your dog based on weight and condition.

Important: Always consult your veterinarian before giving your dog any medication.
Please enter a valid weight between 1 and 200.
Please select Benadryl strength.

Benadryl Safety Guide

Benadryl (diphenhydramine) can be used for dogs to treat:

  • Allergies: Environmental allergies, itching, hives
  • Mild allergic reactions: Insect bites/stings, vaccine reactions
  • Anxiety: Mild sedation for travel or thunderstorms
  • Motion sickness: With veterinary guidance
Did You Know? Benadryl typically takes effect within 30-60 minutes and lasts 8-12 hours.

When to Avoid
  • Dogs with glaucoma
  • Heart disease or high blood pressure
  • Pregnant or nursing dogs
  • Dogs on certain medications
  • Seizure disorders
Safe Administration
  • Always use plain diphenhydramine
  • Avoid products with decongestants
  • Give with food to reduce stomach upset
  • Monitor your dog after first dose
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Important Warnings
  • Never exceed recommended dosage
  • Plain Benadryl only
    No additional active ingredients
  • Call your vet if unsure about dosage
  • Stop immediately if adverse reactions occur