Famotidine (Pepcid) Dosage for Cats — Calculator by Weight
Dose ranges on this page are published veterinary references for education only. Your veterinarian's prescribed dose always wins. When in doubt, call your vet first.
Famotidine (Pepcid) is also used in cats to reduce stomach acid — for gastritis, reflux, ulcers, and vomiting. Published veterinary references list the same standard range as dogs: about 0.5–1 mg per kg, given every 12–24 hours.
Cats with kidney disease are commonly prescribed famotidine, but dosing in kidney patients must be set by a veterinarian. Use the calculator below as a reference, and confirm with your vet before dosing.
Dose calculator
Dosage chart by weight
| Cat weight | Dose range per dose |
|---|---|
| 5 lb | 1.1–2.3 mg |
| 8 lb | 1.8–3.6 mg |
| 10 lb | 2.3–4.5 mg |
| 12 lb | 2.7–5.4 mg |
| 15 lb | 3.4–6.8 mg |
| 18 lb | 4.1–8.2 mg |
| 20 lb | 4.5–9.1 mg |
Chart uses the same conservative range as the calculator (0.5–1 mg per kg of body weight (conservative range)). Always confirm with your veterinarian.
Common formulations
- Tablets — 10 mg tablets
Usually split into quarters/halves for cats — confirm with your vet
Use the calculator above to convert any of these sizes into an amount for your pet's weight.
How often to give it
Every 12–24 hours. 0.5–1 mg per kg of body weight (conservative range).
Common veterinary uses
- Acid reflux
- Gastritis
- Stomach ulcers
- Vomiting (vet-directed)
- Stomach protection in chronic kidney disease (vet-directed)
Safety warnings
Possible side effects
- Usually well tolerated
- Rare: decreased appetite, mild vomiting
- Use PLAIN famotidine only — avoid combo products with extra active ingredients.
- Tell your vet about all other medications your cat takes.
Do not use (or ask your vet first)
- Cats allergic to famotidine or cimetidine
- Cats with kidney disease need vet-set dosing — do not guess
When to see a veterinarian
- Vomiting blood or coffee-ground material
- Black, tarry stools
- Persistent vomiting or complete refusal to eat for 24 hours
- Lethargy, hiding, or collapse
- Your cat has kidney disease — dosing must be vet-directed
Frequently asked questions
How much Pepcid can I give my cat?
Published references use about 0.5–1 mg/kg every 12–24 hours. A 4 kg (9 lb) cat would be roughly 2–4 mg per dose — a fraction of a 10 mg tablet. Because cat doses are tiny, confirm with your vet.
Is famotidine safe for cats with kidney disease?
It is commonly prescribed for cats with chronic kidney disease, but the dose and frequency must be set by a veterinarian — kidney patients clear drugs differently.
Can I give my cat Pepcid daily?
Only under veterinary direction. Long-term use needs monitoring, especially in cats with other conditions.
What if my cat spits out the tiny tablet piece?
Ask your vet or pharmacist about compounding options — tiny fractions of tablets are hard to dose accurately at home.
Sources
- GoodRx — Pepcid (Famotidine) for Dogs (dosing background)
- SingleCare — Famotidine for Dogs: Dosage Chart
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Dose ranges on this page are published veterinary references for education only. Your veterinarian's prescribed dose always wins. When in doubt, call your vet first.