Benadryl for dogs dosage chart
| Weight | Usual dose | Range (2 to 4 mg/kg) | 25 mg tabs | Liquid (2.5 mg/mL) |
|---|---|---|---|---|
| 5 lb | 5 mg | 5 to 9 mg | ¼ | 2 mL |
| 10 lb | 10 mg | 9 to 18 mg | ½ | 4 mL |
| 15 lb | 15 mg | 14 to 27 mg | ½ | 6 mL |
| 20 lb | 20 mg | 18 to 36 mg | ¾ | 8 mL |
| 25 lb | 25 mg | 23 to 45 mg | 1 | 10 mL |
| 30 lb | 30 mg | 27 to 54 mg | 1¼ | 12 mL |
| 35 lb | 35 mg | 32 to 64 mg | 1½ | 14 mL |
| 40 lb | 40 mg | 36 to 73 mg | 1½ | 16 mL |
| 50 lb | 50 mg | 45 to 91 mg | 2 | 20 mL |
| 60 lb | 60 mg | 54 to 109 mg | 2½ | 23.9 mL |
| 70 lb | 70 mg | 64 to 127 mg | 2¾ | 27.9 mL |
| 80 lb | 80 mg | 73 to 145 mg | 3¼ | 31.9 mL |
| 90 lb | 90 mg | 82 to 163 mg | 3½ | 35.9 mL |
| 100 lb | 100 mg | 91 to 181 mg | 4 | 39.9 mL |
| 120 lb | 120 mg | 109 to 218 mg | 4¾ | 47.9 mL |
How to use this chart
Find your dog's weight, or the nearest row below it if you're between two. The "usual dose" column is about 1 mg per pound, where most vets start. Give it no more than every 8 hours and no more than 3 times in 24 hours.
Tablet amounts are rounded to the nearest quarter. If that's too fiddly for a small dog, use the liquid column with an oral syringe. Pick a children's liquid that contains only diphenhydramine and no xylitol.
Before you give the first dose
Call your vet if your dog has never had diphenhydramine, takes other medicines, or has heart disease, glaucoma, seizures, or a prostate or thyroid problem. If your dog's face is swelling quickly or it is struggling to breathe, skip the chart and go straight to an emergency vet.
Frequently asked questions
Is the Benadryl dosage for dogs 1 mg per pound?
Yes, roughly. 1 mg per pound equals 2.2 mg per kg, which sits at the low end of the vet range of 2 to 4 mg/kg. It is the dose most vets start with.
What is the maximum Benadryl dose for a dog?
The top of the standard range is 4 mg per kg (about 1.8 mg per pound) per dose, no more than every 8 hours. Never go above that without a vet’s instruction.