Benadryl Dosage Chart for Dogs (by Weight)
A printable Benadryl dosage chart for dogs based on the standard 1 mg per pound rule, from 5 lb to 100 lb — plus how to dose with tablets vs liquid.
This chart uses the standard 1 mg of diphenhydramine per pound of body weight. For your dog’s exact weight (and to switch between tablets and liquid), use the interactive Dog Benadryl Dosage Calculator.
Benadryl dose by weight (25 mg tablets)
| Dog weight | Dose | 25 mg tablets |
|---|---|---|
| 5 lb | 5 mg | use liquid |
| 10 lb | 10 mg | ~½ tablet / liquid |
| 15 lb | 15 mg | ~½–¾ tablet |
| 20 lb | 20 mg | ~¾ tablet |
| 25 lb | 25 mg | 1 tablet |
| 30 lb | 30 mg | ~1 tablet |
| 40 lb | 40 mg | ~1½ tablets |
| 50 lb | 50 mg | 2 tablets |
| 75 lb | 75 mg | 3 tablets |
| 100 lb | 100 mg | 4 tablets |
Give every 8–12 hours, up to 2–3 times per day.
Tablets vs. liquid
- Tablets (25 mg): simplest for medium and large dogs.
- Children’s liquid (12.5 mg / 5 mL): best for small dogs and precise dosing — much easier than cutting tablets into quarters.
Whichever you use, it must be plain diphenhydramine — no decongestants, no acetaminophen, no xylitol.
Educational reference only — not veterinary advice. Confirm your dog’s dose with your veterinarian.