What this calculator does
This tool estimates how much famotidine (brand name Pepcid) a dog may need based on its body weight. Famotidine is an H2-receptor antagonist commonly used to reduce stomach acid and help manage conditions such as acid reflux, gastritis, and stomach ulcers in dogs. The standard canine reference dose is about 0.5 mg per kilogram of body weight, given every 12 to 24 hours. This calculator is for educational reference only and does not replace veterinary advice.
How to use it
Enter your dog's weight and choose pounds or kilograms. The default dose rate is 0.5 mg/kg, but your vet may recommend a value within roughly 0.5–1.0 mg/kg depending on the condition. The calculator returns the dose in milligrams for a single administration, which you would typically give once or twice daily as directed.
The formula explained
The math is simple: $$\text{Dose (mg)} = \text{Dose Rate (mg/kg)} \times \text{Weight (kg)}$$. If you enter weight in pounds, it is first converted to kilograms by multiplying by 0.4536. For example, a 22 lb dog is \(22 \times 0.4536 \approx 9.98\) kg.
Worked example
Suppose you have a 10 kg dog and use the standard 0.5 mg/kg rate: $$0.5 \times 10 = 5 \text{ mg}$$ per dose, given every 12–24 hours. Pepcid tablets are commonly sold in 10 mg and 20 mg strengths, so your vet may advise splitting a tablet to reach the correct amount.
FAQ
Is Pepcid safe for dogs? Famotidine is widely used in dogs, but you should always confirm the dose, product (avoid combination formulas with extra active ingredients), and duration with your veterinarian.
How often can it be given? Typically every 12 to 24 hours. Your vet will set the exact frequency based on your dog's condition.
What if my dog is very small or very large? Always verify with a vet, especially for tiny breeds, puppies, pregnant dogs, or dogs with kidney or liver problems where dosing may need adjustment.
