Veterinarians usually prescribe between .22 milligrams and .5 milligrams of Pepcid AC per pound for dogs. This drug is not approved by the United States Food and Drug Administration for use on pets, but it is commonly prescribed by veterinarians.

Pepcid AC, also known as Famotidine, is an antacid that blocks the H2 receptors. This reduces the amount of acid in the stomach, which is helpful for preventing heartburn and gastroesophageal reflux disease and healing ulcers. Pepcid AC is an over-the-counter medication developed for human use.

Pet owners should have their dogs checked out with a vet before giving Pepcid AC. Ask about using this medication for the treatment of a specific stomach ailment. Be aware that Famotidine can interact with other antacids, metoclopramide, Sucralfate, digoxin and ketoconazole.

The suggested dose for dogs ranges from .22 mg. to .5 mg. per pound given every 12 to 24 hours. Pet owners may want to err on the side of a lower dose for smaller dogs and larger doses for big dogs. Like with human medication, if pet parents forget to give a dose, make sure to give the regular dose as soon as it is remembered. However, if it is close to time for the next dose, just give the regular dose at the scheduled time.