There are plenty of sites that say "even indoor cats should be dewormed", but since there are plenty of people selling deworming products, I'm suspicious that this idea was not put about for the benefit of cats. Deworming medications for any animal are hard on the liver.

I'm not inclined to deworm my cat on a regular basis unless I'm sure the benefits outweigh the liver damage.

Please assume the house (actually a flat) is pretty clean, there are no outdoor animals in the house, and the cat is only fed high quality food marketed as cat food.

  • For your interest: There are worms that can issue humans and cats also. So you could bring it home and spread it. (around 1 of 3 humans in western world will have min. once worms without notice it). Additional: worm eggs are very robust. They endure around 4 weeks without water, more with. They can travel on any object from the "outside" into your home. Shoes, trousers, shopping goods, bags... Feb 7, 2022 at 7:11
  • @Allerleirauh I don't doubt that it is possible. My doubt is that it is sufficiently likely that the damage done by the de-worming treatment is a good trade-off.
    – Clumsy cat
    Feb 7, 2022 at 8:54
  • This I can not answer. I do not have many experince with cats, but with toddlers licking every stone outsite... Feb 7, 2022 at 12:08

1 Answer 1


Generally speaking, the damage done by the deworming treatment is always preferable to the damage done by long-term parasite infection.

While it is true that indoor cats run a much lower risk, there is still the possibility of worm eggs being tracked in on shoes, and depending on the building even an indoor cats might have mice on the menu without you even knowing, though that is more likely for a house than a flat.

For an indoor cat living in a flat, especially if you want to avoid giving unnecessary medication but still cover your bases, I would suggest collecting stool samples in regular intervals and having them tested for parasite infection.

While this is a bit more expensive than regular deworming, you get the best of both worlds.

  • And of course if any mice or other rodents get into your house or apartment they can carry worms and the cats will get those when they almost inevitably catch and eat the critter. And you'd likely never know as they don't spit out the bones :)
    – jwenting
    Mar 18, 2022 at 8:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.