Daily How Much

Most dogs get 1 mg per lb of plain diphenhydramine every 8–12 hours, with veterinarian guidance and careful label checks.

Most dogs take diphenhydramine at 2–4 mg/kg every 8–12 hours, but your vet should set the dose for your dog.

A common starting point is 1 mg per pound, so a 20-lb dog often lands near a 20 mg dose, spaced about every 8–12 hours.

A typical single dose for a 15-lb dog is 15 mg of diphenhydramine, spaced at least 8–12 hours apart unless a veterinarian tells you otherwise.

Most 10-lb dogs land near 10 mg diphenhydramine per dose, but the safest number depends on the exact product and your dog’s health.

A 70-lb dog often gets 32–64 mg diphenhydramine per dose, spaced 8–12 hours, after a vet says it’s OK.

Most dogs take diphenhydramine at 1 mg per lb (2–4 mg/kg) every 8–12 hours, with a plain “diphenhydramine only” product and a veterinarian’s direction.

Most vets dose diphenhydramine at 2–4 mg/kg per dose each 8–12 hours, using plain diphenhydramine only.

Most vets use 2–4 mg/kg every 8–12 hours, but puppies should get a veterinarian’s OK and a low-end, weight-based dose.

A common starting dose is diphenhydramine 1 mg per pound per dose, given every 8–12 hours, once your vet says it fits your dog.