Why do indoor cats need deworming?

As vets, one of the questions we hear really often is “But she’s an indoor cat! Why do indoor cats need deworming??”. Most people think that because they have an indoor kitty, they do not need to worry about their cat getting worms. Unfortunately, this is not always the case. In fact, indoor cats can (and often do) get worms – even if they do not go outside* (I have a few studies at the end if you want to read more).

Because I get this question so often, I wanted to include it in my blog. So if you also wonder why indoor cats need deworming, this one is for you ☺️

This post may contain affiliate links, which means I may receive a commission, at no extra cost to you, if you make a purchase through a link. Please see my full disclosure for further information.

While I am a veterinarian, this article is not intended to replace professional veterinary advice. If you have any medical concerns about your pet, consult your vet immediately. Always seek professional assistance if you are unsure of your pet’s health.


What exactly are worms

To put it simply, worms are parasites. They live inside the host body and feed on its resources. They do not do any good to the host and can make your cat very sick. They can even kill your kitty if left untreated for long enough. 

Cats can get different types of worms, sometimes even simultaneously. 

The most common types of intestinal parasites in cats are 

  • Roundworms
  • Tapeworms
  • Hookworms

Some not-so-common types of worms are for example whipworms or heartworms.

How does an indoor cat get worms?

You probably have an idea how outdoor cats get worms. By eating rodents and other weird stuff, right? Yep, that’s right.

Outdoor cats can get infected by eating rodents and other small animals they kill. They also come in contact with other cats, as well as infected feces, which is why the risk of contracting a parasitic infection is much higher for outdoor cats. 

However, not all parasites have small rodents as hosts… 

Let me start at the beginning. 

How does a cat get infected with worms? 

By coming in contact with the parasite eggs or larvae. That’s the key.

Depending on the type of worm, there are different ways this can happen – by coming in contact with contaminated feces, by eating infected animals (mice, birds, and such), or by getting bitten by an intermediate host. 

As you can see, there are several possibilities for how an indoor cat can get worms and that’s why even indoor cats need deworming. 

printable cat planner

So how can indoor cats get worms?

Some eggs can lay dormant for months. Even when your indoor cat stays inside all the time, you and other family members go out regularly. So you can actually bring microscopic parasitic eggs home on your shoes and your clothes. Surprising, right? 😊 But true…

Insects and common house pests often harbor parasitic eggs. Did you know that your cat can get roundworms by catching a common housefly? Or by getting bitten by a flea?

Mosquitos and ticks can infect your cat with parasites by biting her. And fleas are actually a significant reservoir for tapeworms. 

The risk of your indoor cat getting worms is much higher if you have a dog. You should always deworm your indoor cat at the same time you deworm your dog. 

If you have more cats, it’s enough for one to get infected, soon all your cats will be positive, trust me 🤷‍♀️

do indoor cats need deworming? How can an indoor cat get worms

Symptoms of worms in cats

Most cats do not show any symptoms of having worms and the only way to find out if your cat is infected is by doing regular worming tests from a stool sample.

In general, the symptoms depend on the type of worm and how bad the infection is.

Some common symptoms of roundworms and hookworms are:

  • Dull coat 
  • Loss of appetite 
  • Weight loss 
  • Vomiting 
  • Diarrhea 
  • Abdominal pain 
  • Enlarged abdomen

However, as I said before, most cats don’t show any symptoms unless the infection is massive and causes serious health problems. 

Why do cats need deworming? And why is deworming your pet so important for your family?

Deworming is an important part of responsible pet ownership. While indoor cats do not get exposed to the same risks as outdoor cats, they can still get worms and require regular deworming. 

Worm infestation can cause serious health problems and even death. And as you can see, even indoor cats can get worms and suffer from related health issues. 

On top of that, worms are zoonoses – diseases that humans can contract from animals. Which basically means YOU OR YOUR KIDS CAN GET WORMS from your cat. That’s why it’s so important, especially if you have small babies or young kids.

Here are a few basic rules to protect yourself and other family members from parasites:

  • Never let your kids touch your kitty’s litter box
  • Wash your kids’ hands thoroughly if they were playing outside in a sandbox
  • Wash your hands thoroughly (you know, corona-style 🙂 ) after cleaning your cat’s litter box
  • Wash your hands thoroughly if you have been gardening without gloves
  • If you are pregnant, let someone else take care of your cat’s litter box and deworm your cat every 3 months. 
  • If you or someone in your family has immunity issues or if you live with elderly family members deworm your cat every 3 months and talk to a doctor about owning a cat.

As I said before, animals can have worms and not show any kind of symptoms. That’s why regular deworming is so important. 

How to properly deworm your cat

The best way to deworm your cat is to use certified dewormers

Sometimes people don’t want to deworm their cat because they are just not able to give her a deworming pill. And I get it. I know what it’s like when a cat turns into a raging killing machine and all you can do is to run for your life… 😾

But the good news is, now there are products called spot-ons that you can put in your cat’s fur, yay! They get resorbed into the skin and are very effective against internal parasites. And they are perfectly safe for you and your kitty, don’t worry ☺️

You can use for example Droncit spot-on for cats, it’s very easy to apply and effective 🙂

Here is a discount for you: If you buy your wormers on, as a first-time customer you can get 20% Extra Off + Free Shipping Sitewide. Use the coupon BVC1ST at checkout 😎

Talk to your vet about which deworming product is best suited for your cat. 

How often should you deworm your cat?

Your vet will be able to tell you the right schedule for your cat. Generally, kittens should be dewormed every two weeks until they are 12 weeks old. After that, they should be dewormed every 3 months until they are six months old. 

Adult cats should also be dewormed at least one time per year or when the veterinarian recommends it.

Home remedies and natural dewormers

I know there are many natural dewormers you can buy online. And I can promise you, every vet on this planet would tell you the same thing regarding natural dewormers – don’t use them. In best-case scenarios, they won’t work enough to completely kill all the parasites and larvae. In the worst-case scenario, your cat will end up dead. Sorry (not sorry 🤷‍♀️). 

I’ve seen people recommend garlic (which is toxic to cats), tea tree oil (also highly toxic to cats), turmeric, pumpkin seeds, and other things.

When I was doing my internship at our University, we had a cat that barely survived a tea tree oil anti-parasitic “treatment”. She was completely bald and was coming for regular infusions because even 2 weeks after being released from the hospital she still wasn’t ok.

So please, please, please at least talk to a vet before you use something you found on google. 

cat planner

How to prevent your indoor cat from getting worms

The best way to prevent your indoor cat from getting parasites is to do regular deworming. Your vet can tell you how often you need to do it, but in most cases, it’s every 3-6 months. 

You should also inspect your cat’s stool for any worms or eggs (they look like tiny white specks) and take her to the vet if you spot anything.

If you have a doggy in the house, deworm him regularly as well. 

Wash your hands after gardening and try to keep your cat away from other animals (mice, birds… you would be surprised what an indoor cat is able to catch on the balcony). 

Remove the feces from your cat’s litterbox daily, and wash the litterbox with a disinfectant on a regular basis. 

Avoid overcrowded conditions. If you have more cats, each should have her own litterbox.

Don’t give your cat raw meat. But if you really want to, buy meat suitable for human consumption or freeze it for at least 2 days. 

Try to control intermediate hosts like flies, ticks, mosquitos, or fleas. 

Last but not least, take your cat to a vet at least once a year for a regular check-up ☺️

In conclusion, do not forget that indoor cats can still get worms, and regular deworming is essential for all cats, regardless of whether they spend most of their time indoors or outdoors. 

Even if your cat seems healthy, a vet checkup and deworming can help keep her from getting sick in the future. This is an essential part of responsible pet ownership and will ensure your kitty stays happy and healthy for years to come. 

I hope this answers your question about why your indoor kitty needs deworming ☺️

PS: If you are as crazy about animals as I am, subscribe to my newsletter! Now you will get a cute printable cat planner as a bonus 

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  • Amanda

    This is so useful, I didn’t know an indoor cat could get worms! Also, I love your infograph with the white kitty! It is adorable <3

  • Lizzy

    This is actually a question I always wondered about, so I was so pleased to see you answered it. Thanks! Im hoping to get an indoor cat in the next year so I’ll be sure to worm him regularly. That’s so gross that we can take the eggs into the house on our clothes and shoes! Hoping I can get that image out of my head soon! 😜

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