Famotidine (Pepcid)
An H2-receptor antagonist that reduces gastric acid secretion to soothe stomach upset, ulcers, and acid reflux.
💬 In Plain English
Famotidine (commonly known by the human brand name Pepcid) is an antacid medication that belongs to a class of drugs called H2-receptor antagonists. It works by blocking histamine receptors on the acid-producing parietal cells of the stomach lining, effectively turning down the stomach’s acid spigot. Veterinarians use famotidine to protect the stomach from ulcers, ease heartburn and acid reflux, treat mild gastritis, and settle nausea in pets with kidney failure. While helpful for mild symptoms, newer proton-pump inhibitors (like omeprazole) suppress stomach acid far more potently.
🔬 Clinical & Technical Depth
For Vets & TechniciansFormal Clinical Definition
Competitive, reversible inhibitor of histamine H2-receptors on gastric parietal cells, suppressing basal and stimulated gastric acid and pepsin secretion.
Why Veterinarians Use It
Veterinarians use famotidine as an adjunctive oral or injectable gastric protectant in managing gastritis, reflux esophagitis, and uremic gastritis.
Clinical Context Encountered
Given as oral tablets or veterinary clinic subcutaneous/intravenous injections for vomiting pets.
Clinical Reference Guide (Veterinary Medication)
What Owners Must Know
- Administer 30 to 60 minutes before meals for optimal effect
- Tachyphylaxis (diminished drug efficacy) often develops after 10–14 days of continuous administration
- Only use plain famotidine; avoid chewables with xylitol.
Potential Side Effects
- Extremely rare; mild transient diarrhea, bradycardia (if rapid IV injection given)
- •Always check the ingredient label of over-the-counter human Pepcid products: NEVER use combination products (like Pepcid Complete) that contain chewable artificial sweeteners like xylitol (fatal to dogs).
❓ Questions to Ask Your Veterinarian
Take these actionable questions with you to your next clinic visit or appointment:
- 1Is famotidine sufficient, or would a proton pump inhibitor like omeprazole provide superior acid suppression?
- 2Can famotidine be given with my pet’s other heart or antibiotic medications without drug interactions?
- 3Does the dose need to be adjusted downward if my pet has kidney disease?
Academic & Clinical References
- Antiulcer Agents and Gastrointestinal Protectants in Veterinary MedicineOrganization: Merck Veterinary Manual • Accessed: 2026-01-10https://www.merckvetmanual.com