Diagnosing if a Cat has Worms

Your cat was probably born with worms but was hopefully wormed before you got it.  If your cat goes outside, eats mice, or is exposed to other animals (including fleas), it probably has worms.

Tabby cat ©BN

Tabby cat ©BN

There are many types of worms that infect cats, some are more common than others depending on where you live. You may see worms feces and know without a doubt that your cat has worms, otherwise the best way of determining if a cat has worms is through a fecal test done by a veterinarian.

To get your cat tested for worms you do not have to take it to the veterinarian, you can just bring in a fresh stool sample in a sealed plastic bag. The veterinarian can usually let you know fairly quickly if your pet has worms and can offer a treatment. The vet is not looking for worms in the feces, but is looking for worm eggs.  It is very important to get the correct diagnosis from a veterinarian as over the counter worming medications do not kill all types of worms and until you know what kind, or kinds, of worms your cat has, you will be wasting your money.


Tapeworms are segmented animals which get long inside the body and then shed segments of themselves. They are flat and can grow up to two feet long. Owners may see small rice like things on their cat’s rump or tail, these are often tapeworm segments. Cats who catch mice or have fleas may get tapeworms. Fleas can harbor tape worm eggs and cats who swallow fleas when they itch themselves will ingest these eggs.


These are fairly common in cats, and range from white to brown in color. They grow to several inches in length. A bad infection may even have a cat vomiting these worms, but it is more likely to find them in a cats stool. Roundworms can be passed from mother cats to their kittens through their milk, and as such are very common in kittens, particularly barn kittens. Cats may appear to have pot bellies, but this should never be used as a diagnosis measure alone.


These worms are named so because of a hook shape on their mouth which attaches them to the cats intestines. Hookworms can cause diseases in cats and when transmitted to kittens they often cause death of the animal.


These are more common in dogs than in cats, but cause similar symptoms, such as coughing after exercising, and even death.  Heartworms are spread by mosquitoes so are more common in outdoor cats.  There is no way to treat heartworm in cats.

Symptoms of Worms in Cats

The main symptom of worms, with the exception of heartworm, is that the cat will have diarrhea, particularly concerning is if it is bloody, or worms can actually be seen. This is one of the reasons it is important that owners provide a litter box for their pet and clean it regularly. Cats who use the outdoors for a litter box may be suffering from infections long before anyone is aware.

As mentioned occasionally worms will actually be seen but by this time the cat is suffering from a heavy infection. Vomiting can also be a symptom of worms. Depending on the type of worm involved the cat may appear to have a pot belly, may loose weight, or may simply not show any symptoms at all. As such a regular veterinarian check is a good idea, particularly checks should be done on cats who go outdoors. Keeping the cat on a regular worming schedule is important for cats who are exposed to mice and other avenues of contracting worms.

Note that ringworm is not a worm, but is a fungus, to learn more about ringworm in pets, click here.

Originally published November 15, 2009 at http://www.helium.com/items/1651750-how-to-tell-if-a-cat-has-worms