What Medication Is Used to Treat Stomach Worms in Cats?

A kitty with worms may lose her appetite.
i Ryan McVay/Photodisc/Getty Images

There are many types of worm-like parasites that can infect your kitty, usually targeting her intestines or stomach. Once infected, your furry friend may experience stomach upset, vomiting or diarrhea, among other signs of illness. A kitty with stomach worms needs special medication to rid her of them.

Types of Stomach Worms

While more common feline parasites like roundworms, hookworms or tapeworms usually attach themselves to the intestines of your kitty, less common ones affect the stomach. Parasitic stomach worms that can affect your kitty include Ollulanus tricuspis, Aonchotheca putorii, Physaloptera praeputialis and Physaloptera rara, according to "Companion and Exotic Animal Parasitology." These tiny worms are types of nematodes that infect your kitty's tummy where they feed on her nutrients and blood, causing her inflammation and discomfort. These worms won't resolve on their own and need veterinary treatment to eradicate them.


To treat a stomach worm infection, your vet will prescribe one of several medications to kill both the worms and their eggs. The medication used will depend on the type of worm your vet discovers through a test of her feces or vomit. Once the type of worm is diagnosed, your vet will prescribe or administer anthelmintic medications, which kill internal parasitic worms. Of these drugs, tetramisole can be used to treat Ollulanus tricuspis, while levamisole and ivermectin can rid your kitty of both Aonchotheca putorii and Physaloptera praeputialis in the stomach. The common dewormer pyrantel pamoate can be used to treat Physaloptera rara nematodes. In addition to these medications, your vet may also prescribe anti-inflammatory drugs or antibiotics to treat inflammation or secondary infections, depending on your kitty's condition.


Depending on the anthelmintic medication prescribed, your vet will either administer the drug during your visit through an injection or orally. He may also give you an oral medication to take home with you to give your kitty. Some of these medications require more than one dose, either several hours or a few weeks apart. For oral medications like pyrantel pamoate, you can mix them into your furry friend's canned food, or they may come in flavored tablets that you feed directly to your kitty. Your vet will determine the correct dosage, based on your kitty's weight. He will also instruct you on how to administer the drug to your kitty, and how often. Some kitties may need treatment with more than one type of medication, especially if more than one type of parasite is present.

Side-Effects and Rechecks

Side-effects are possible with the medications used to treat stomach worms. These include vomiting and excessive salivation, so monitor your furry buddy after treatment for unusual signs and let your vet know what they are. Never give your kitty a larger dose of an anthelmintic medication than prescribed by your vet because this can result in a potentially fatal toxic reaction, according to PetPlace.com. See your vet for a recheck of your kitty after the course of her medication is over. He will retest your furry friend for any signs of the parasites to determine whether further treatment is needed. Keep your kitty indoors to prevent her from becoming re-infected, and have her checked at the first sign of recurrence.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

the nest