Is it necessary to deworm an indoor cat?

Do indoor cats get worms? How often should I deworm my indoor cat? These are 2 very common questions we get from cat parents. There is a popular myth that indoor cats are never exposed to intestinal parasites and therefore, there’s no need to deworm them. But that is not true.

In this article, you’ll learn why your cat needs to be wormed, the 4 ways your indoor cat can get worms, signs your cat has worms, and how to prevent your cat from getting worms.

Orange kitten in the gloved hands of a veterinarian seemingly asking Do indoor cats get worms?
Will you protect me from worms and other parasites?

Table of Contents

Why do cats need to be dewormed?

All cats can become infected with various types of intestinal parasites. The different types of worms include roundworms, hookworms, tapeworms, and more. These intestinal parasites can cause a range of health issues for your cat. These include weight loss, diarrhea, vomiting, and even death in severe cases. Giving your cat deworming medicine regularly is an important step in preventing these health problems and keeping your cat healthy.

The most common parasites we see are ear mites and roundworms.  Both are easily detected and dealt with by your veterinarian.  Heartworm disease is a more devious parasite. In a study, 4% of all cats and 28% of dogs have heartworm disease. Your pet can get heartworms from a mosquito bite.  They are called heartworms because they live in your pets body (cat and dogs).  They live in the heart, lungs, and blood vessels surround these organs.  Left unchecked, they can be fatal. 

Ways your indoor cat can get worms

  1. Fleas. Fleas are parasites, but they can also have parasites of their own such as tapeworms. Isn’t nature amazing? In fact, infected fleas are a common carrier of cat, dog and human internal parasite larvae. When a cat or a dog ingests a flea or rodent infected with tapeworms, the larvae travels to their next host—your pet. It’s fairly common for a dog to lick their owners face or for a cat to take food from their owner’s plate (without permission), in which case the larvae can travel to their human (you), but that’s another story. Where does an indoor cat get fleas? Fleas are often carried indoors on our shoes or clothes, and it doesn’t matter if your house is very clean or even spotless. You wouldn’t likely notice a single flea (it might not even bite you), but a flea would make a beeline straight for your cat (or dog) once it came inside.
  2. Worm eggs. Several parasite species propagate by having host animals ingest their eggs, which are found in the environment. Worm eggs are often brought indoors on our shoes and clothes. Is your cat sniffing around your outdoor boots to check where you’ve been? Most cats do check out shoes (like ours), as they are curious animals. And we all know what curiosity does to the cat; it gets them worms. To help prevent this, keep your house clean and store outdoor clothing and footwear out of your cat’s reach. Roundworm eggs can be found in the feces of an infected animal. Ingesting the feces is how your pet gets infected.  Roundworms are one of the most common type of worm infection we see in our clinic.  Most often we see them in kittens that got the roundworm eggs passed to them from their mother while nursing. The most common clinical signs include a vomiting, a pot bellied look, abdominal pain, reduced appetite, a dull coat, and diarrhea. You may also notice them in their stools.  One of our cats ate some lawn grass clippings. She later threw up and there were roundworms wiggling in it. That was an easy diagnosis.
  3. Other pets. Do you have other pets that go in and out? Maybe your dog (or in our case, dogs) that you take for regular walks? Even if they aren’t infested themselves, that pet can pick up a few or other parasite and transmit parasites to your indoor pets or cats in this example.  They can transmit the parasite to their house mates easily. They share the same environment and parasites are experts at infiltrating a new environment and finding viable hosts. In practicality, this means that when one of your pets has worms, others are possibly susceptible. When you administer deworming medication to one of your cats (or pets) it’s best that you simultaneously do the same for all the other animals in your home. Remember, deworming is purging. It doesn’t provide immunity against future contact with different types of worms. Therefore it’s best to minimize future cases by taking preventative measures to ensure that none of your pets get worms. We recommend parasite prevention medicine to our patients in our vet clinic.  Please consult with your veterinarian for a recommendation to deworm and preventative medication.
  4. Food. Even if you have an indoor cat, if they are let outside to roam your yard, they can consume an infected rodent or bird. Are you feeding your cat a raw diet? We don’t discourage this. If you do it right, it can provide premium nutritional balance for your cats. If you like to give snacks to your cat, raw meat is typically the best option. However, raw meat is also a way for indoor cats to get worms. It’s not that common, but still possible. The good thing is, the risks are negligible if you select sources of ingredients carefully and comply with hygiene guidelines during the preparation process.
  5. The frequency of deworming your indoor cat will require depends on various factors such as their age, lifestyle, and the level of risk for getting infected with internal parasites. Kittens, for example, should be dewormed more frequently than adult cats because they are more susceptible to parasites.
  6. Generally, it is recommended that indoor cats be dewormed at least once or twice a year. However, the best way to determine the ideal deworming schedule for your cat is by consulting with your veterinarian. They will consider your cat’s individual risk factors and recommend a deworming schedule that is appropriate for them.
an indoor cat getting his worm medicine - not happy about it
Indoor cats need to get worming medicine too — no matter how much they don’t want it. Photo by Erik Newth, creative commons

Signs that your indoor cat needs deworming

While it’s important to follow a regular deworming schedule, you should also be aware the symptoms of worms that your cat may have internal worms. Some of the most common signs include:

  • Weight loss
  • Vomiting
  • Diarrhea
  • A distended or bloated belly
  • Dull coat or dry skin and coat
  • Lethargy or weakness
  • An increase in appetite
  • Scooting or rubbing their anus on the carpet is a sign of tapeworms
Roundworms in cat feces
Cat feces with roundworms

Also if you notice roundworms that look like spaghetti in their stools, your cat is infected. Tapeworm segments in an infected pets stool look like grains of rice. If you notice any of these symptoms in your cat, it’s important to contact your veterinarian right away. They can take a fecal sample and do a fecal exam to check for parasites and recommend appropriate treatment.

How do I keep my cat parasite free?

Administering a broad based parasite prevention medication, regular deworming, and flea and tick control. Here are steps you can take to prevent parasite infestations in your indoor cat. Some of these include:

  • Keeping their litter box clean
  • Feeding them a high quality diet
  • Keeping their environment clean and free of pests
  • Preventing them from hunting or eating rodents and other wildlife
  • Regular flea treatment (and tick)
  • Regular grooming and inspection of your pet to remove any fleas or other parasites. Especially after any outdoor trips. We recommend a flea comb
  • And of course, administering parasite preventative medicine regularly

How often do I deworm my indoor cat?

Indoor cats have a smaller smaller risk to get parasites compared to that of outdoor cats; however, most veterinarians (like us) suggest to deworm indoor cats as frequently as outdoor cats. Why?

This is because it’s not possible to tell when your cat will be exposed to worm eggs or larvae again; therefore, you must provide preventive medicine on a regular basis.

How often should you deworm an indoor cat? This depends on several factors, such as where you live, how clean you keep your home, what other pets live in your household, what medicine do you give them, etc. Most commonly, cats require deworming anywhere between every three to twelve months (note: one deworming consists of two medications, usually administered two weeks apart). Talk to your veterinarian about the schedule that suits you best.

Remember, keeping your cat indoors does not eliminate the risk of getting parasites. Although indoor cats have reduced risk, the risk is still here, and plausibly high. Therefore, regular deworming and preventative parasite medication are the best lines of defense if you want to keep your indoor cat free of parasites.


Preventative parasite medication and deworming your indoor cat is an essential aspect of their healthcare routine. While there isn’t a one-size-fits-all answer to how often to deworm your cat, consulting with your veterinarian is the best way to determine a schedule that is best for your cat’s individual needs. By following a regular deworming schedule and taking steps to prevent infestations, you can help ensure your cat stays healthy and happy for years to come.

You have learned why your cat needs to be wormed, the 4 ways your indoor cat can get worms, signs your cat has worms, and how to prevent your cat from getting a worms. This will go a long way towards a healthy and happy life with your pet cat.  And keeping your Pet Happy is what we all want.


Question: Do indoor cats get worms?

Answer: Yes. Indoor cats can get worms. Although they are less likely to be exposed to parasites, there are still several ways they can become infected, such as through fleas, worm eggs brought in on clothing or shoes, contact with other pets, and eating infected prey or raw meat.

Question: How often should I deworm my indoor cat?

Answer: The frequency of deworming your indoor cat will depend on factors such as their age, lifestyle, and the level of risk in your area. Please consult with your veterinarian to determine the appropriate deworming schedule for your cat.

Question: What are the types of worms that cats can get?

Answer: Cats can get several types of worms, including roundworms, hookworms, tapeworms, and more.

Question: What are the signs that my cat has worms?

Answer: Signs that your cat may have worms include weight loss, diarrhea, vomiting, a pot-bellied appearance, a dull coat, and abdominal pain. You may also see the worms in your cat’s feces or vomit.

Question: How can I prevent my indoor cat from getting worms?

Answer: To prevent your indoor cat from getting worms, you can take several measures, such as keeping your house clean, storing outdoor clothing and footwear out of your cat’s reach, using flea & tick prevention, regular deworming medication as recommended by your veterinarian, and minimizing your cat’s contact with other pets or infected prey.

Question: Can cats get heartworm disease?

Answer: Yes. Cats can get heartworm disease from a mosquito bite. Heartworms live in the heart, lungs, and blood vessels surrounding these organs, and they can be fatal if left unchecked.

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