Cimetidine for Cats

Cimetidine is one form of a group of drugs called H-2 blockers. Other generic forms that you may be familiar with are ranitidine, famotidine and nizatadine, although you may know them better by the brand names Zantac, Pepcid and Axid. These are all anti-ulcer drugs that block the histamine H-2 receptor that stimulates the production of stomach acid. Cimetidine was one of the first drugs of this type on the market but, according to the Veterinary Drug Handbook, vets use cimetidine less frequently now that other H-2 blockers are available. This is due to the fact that ranitidine and famotidine have fewer interactions with other drugs and fewer doses are needed. Cimetidine is not FDA-approved for treating animals, but vets are legally allowed to prescribe it as an "extra-label" drug.

Your vet is most likely to prescribe cimetidine to prevent your cat developing a stomach or intestinal ulcer. However, the drug has other uses. A feline friend with kidney failure may benefit from the drug if she's vomiting and has excess stomach acid, two symptoms associated with a chronic renal problem. However, because cimetidine doesn't interact well with amlodipine, a high blood pressure drug, or diazepam, which is used to stimulate a cat's appetite, your vet may use famotidine or ranitidine instead. It all depends what other drugs your cat is taking. Make sure you tell your vet about any other drugs your furry friend is on, to reduce the risk of side effects from a drug interaction. It's also used for acid reflux cases to prevent damage to the esophagus. A vet might also prescribe it to reduce histamine production in a cat with mast cell tumors.

Cimetidine is available in tablet, liquid and injectable forms. According to PetPlace, the typical dosage is 3 to 5 mg per pound of your cat's weight, given every six to eight hours daily. Vets recommend giving the drug on an empty stomach rather than with food, because if you give it with her food her stomach will start secreting acid before the drug has time to work. Your feline friend is quite likely to think cimetadine tastes horrible and you might notice her drooling after you've given it to her. The Veterinary Drug Handbook suggests you ask the pharmacist to add a pleasant flavor to the cimetidine solution as a way of making it less objectionable for your cat.

The Veterinary Drug Handbook says that there are few side effects with cimetidine, but your cat could be allergic to the drug; if you notice anything abnormal, talk to your vet as soon as possible. Vet Eric Barchas says that if your cat does suffer unwelcome side effects these are likely to be a skin rash, disorientation or mental confusion.