Daily How Much

Most dogs are dosed at 1–2 mg per pound per dose, given every 8–12 hours, using plain diphenhydramine only.

Most Tylenol PM caplets contain 25 mg diphenhydramine HCl per caplet, paired with 500 mg acetaminophen.

Typical adult diphenhydramine is 25–50 mg every 4–6 hours, with label limits and a high chance of drowsiness.

Most dogs start at 1 mg of diphenhydramine per pound per dose, given every 8–12 hours, unless your veterinarian sets a different plan.

A common diphenhydramine dose for dogs is 1 mg per lb (2–4 mg/kg), given every 8–12 hours, using plain diphenhydramine only.

For many dogs, diphenhydramine is dosed at 1 mg per pound (2–4 mg/kg) every 8–12 hours, after a vet says it fits your dog.

Most adults take 25–50 mg per dose every 4–6 hours, up to 300 mg in 24 hours, unless a clinician gives different directions.

Most vets start diphenhydramine at 1 mg per lb, but puppies need a vet’s OK, a plain product, and weight-based measuring.

Most dogs take diphenhydramine at 2–4 mg/kg per dose by mouth every 8–12 hours, with a veterinarian setting the safest target for your dog.

Most dogs get diphenhydramine at 1 mg per pound per dose, which equals 0.4 mL per pound when the liquid is 12.5 mg per 5 mL.