16 tips on cat worms and deworming

by Michael Broad · April 12, 2022

Here are 16 tips on cat worms (endoparasites); one of the most unpleasant parasites to bug cats. Although a lot of cats tolerate worms because the most successful worm is the one who does not harm their cat host to the extent that they harm themselves. This is the fundamental principle of all parasites.

Cat has a bug that looks like rice coming out of butt

Two useful tags. Click either to see the articles: Toxic to cats | Dangers to cats

Tapeworm segment looking like rice. Image: PoC.

Deworming medications can be effective against more than one worm species but there is no medication which is effective against all species of worm. Ideally, there needs to be a precise diagnosis as to which worm is infecting your cat.
Accordingly, most veterinarians recommend deworming when there has been a specific diagnosis and evidence of an infestation. This is carried out using a microscopic stool examination.
The above is important because all deworming medications are poisons. They are poisonous to the cat. The presumption is that they are less poisonous to the cat than the presence of the worms.
It’s important, therefore, in an ideal world, to deworm your cat under veterinary supervision.
If your cat has an unexplained illness, it is not advisable to presume that your cat has worms and deworm him or her. This is because cats who are debilitated by an illness may suffer when treated with a poisonous dewormer. They may be unable to resist the toxic effect of the deworming pill.
The above being said, it is reasonable to routinely deworm cats for ascarids and tapeworms who are allowed outside to hunt as they may pick up gastrointestinal parasites (endoparasites) from the animals they prey on. “Ascarids” are worms of the family Ascaridae. Veterinarians would accept that deworming indoor/outdoor cats is acceptable without specifically identifying an endoparasite infestation.
The classic way to identify a tapeworm infestation is to see tapeworm segments attached to the fur around the bottom of an infested cat. They look like rice segments (see picture above).
Cat breeders should have their breeding female cat (a queen) checked for endoparasites before breeding, and if she is infested she should receive a thorough deworming. It will reduce the frequency and severity of any parasitic infestation of her kittens. And it will improve her health which is important during pregnancy.
Reinfestation by endoparasites is commonplace and therefore to keep worms under control it is advisable to destroy the eggs or larvae before they reinfest the cat. This means good sanitation and maintaining a clean healthy environment for cats. And it means controlling intermediate hosts such as the animals that cats prey upon i.e. rodents.
Full-time indoor cats should not receive standard and routine deworming medications. This is because, as mentioned, it is a balancing act to provide your cat with a deworm because it’s a toxic substance.
For cats who can enjoy an outside enclosure, they should not be crowded together on shaded earth because this provides good conditions for the eggs and larvae of worms. Ideally the floor should be watertight; such as made of cement which is also easier to clean. It should be hosed down regularly and allowed to air dry. The surface can be disinfected with lime, borax or salt.
Cats allowed onto lawns should enjoy a lawn which has been cut short to help minimise reinfestation.
A lot of kittens are infested with ascarids but other worm species might be present and therefore a veterinary check as to the species of worm is advisable in order to get a full picture and not miss the treatment of an unidentified worm species.
A worm infestation can kill a kitten. Endoparasites are particularly harmful to kittens when they are subjected to other environmental conditions which are damaging such as chilling, close confinement and a sudden change in diet. These are stressful conditions.
Owners should not presume that a kitten with diarrhoea is suffering from a worm infestation. A veterinary diagnosis should take place.
Kittens with ascarids should be dewormed at 2-3 weeks of age and again at 5-6 weeks of age. A lot of American veterinarians recommend deworming kittens with a SAFE dewormer every month until six months of age.

Fleas involvement in tapeworm lifecycle. Image: PoC.

Cat tapeworm segments and whole worms. Collage: PoC. Pics: in public domain. Drawing: Lifelearn Inc.

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