Healing of acid-related disorders (ARDs; e.g. stomach ulcers, gastroesophageal reflux disease) is dependent on increasing the pH of the stomach juice. Thus, drugs that help to suppress acid production, such as omeprazole (brand name: Prilosec) and famotidine (brand name: Pepcid), are commonly prescribed. In studies in dogs and cats, omeprazole is more effective at raising the pH of the stomach and is often recommended for the treatment of ARDs. However, unlike omeprazole, famotidine can be given with food, is immediately effective, is associated with less adverse effects in people, and has additional healing effects. Thus, famotidine continues to be widely used by feline practitioners. However, we have concerns that continuous daily administration of famotidine administration might lead to development of poor efficacy of the drug in cats.
Indeed, research in humans and preliminary studies in dogs demonstrates that the beneficial effects of famotidine decrease over time, often within 8-14 days. Studies in humans suggest that every other day (“intermittent”) administration of famotidine prevents this decrease in efficacy. As famotidine is widely used by feline practitioners, these primary investigators’ study objectives are to determine if (1) daily administration of famotidine leads to a loss of efficacy of famotidine in cats, and, if (2) every other day administration will prevent the loss of efficacy of famotidine in cats. These findings will be immediately and broadly applicable to veterinarians caring for our feline companions.