How to Deworm Kittens and Cats

Medically Reviewed by Amy Flowers, DVM on November 14, 2022
5 min read

When you hear the word "worm," you’ll likely think about the earthworms you find in your garden bed or under a rock you’ve moved in your yard. Worms that inhabit animals, such as dogs and cats, are very different and, unfortunately, are a common pest. 

Many cat owners realize the importance of deworming their feline friends. It can, quite literally, save your cat’s life to get them dewormed. Kittens are especially susceptible to the serious consequences of worms infesting their bodies. This is because kittens are still small, and their bodies are still developing. Kittens require sufficient nutritional components. Worms feed on their host’s nutrients. Sharing nutritional supplies with these parasitic creatures can harm a kitten's health. 

As a pet parent, it’s important that you understand the types of worms that can infest your cat, the symptoms associated with these worms, the risk factors, and how to treat and prevent worm infestations in your cat. 

Several types of worms can infest your cat’s gastrointestinal tract and other organs. Common cat-based worms include: 

  • Tapeworms: These long and slender worms attach to and attack your cat’s intestines. The worms have several body parts, also called segments, and the segments each have their own reproductive organs. These worms are usually diagnosed when segments, which can look like seeds or grains of rice, are found in a cat’s stool. There are a few different species of tapeworm, affecting different hosts, from fleas to small rodents. When a cat is bitten by a flea or eats a tapeworm-infected rodent, the tapeworm then infects the cat, and the cat becomes its host. 
  • Roundworms: The most common worm found in both cats and dogs is the roundworm, which affects a cat’s intestines. In fact, most cats will become infected during their lifetime with these pests, typically when they’re young kittens. There are many ways that cats become infected with roundworms, including ingesting roundworm eggs, eating infected mice, or consuming an infected mother’s milk. 
  • Hookworms: Hookworms are another type of intestinal parasite that affects your cat’s digestive tract, typically the lining of the intestinal wall. These worms consume your cat’s blood and are passed around through feces and infected soil. These worms are dangerous, especially to young kittens, as they can cause intestinal tract bleeding, which can result in young kittens dying. 

Rarely, your cat may also contract whipworms, stomach worms, and parasites such as coccidia, giardia, or toxoplasma.

How can you tell if a cat has worms? The symptoms your cat experiences will depend on the type and severity of the worm infestation. However, your cat may generally experience nonspecific symptoms, including:

  • Dull coat
  • Coughing, hacking, or wheezing 
  • Vomiting
  • Diarrhea
  • Mucous and blood in stool 
  • Poor appetite
  • Pale mucous membranes
  • A stomach that appears swollen or potbellied
  • Anemia
  • Dehydration 

Heavily infected cats may experience weight loss, irritation of the anus, and a failure to thrive. Although rare, some parasites can be passed from cats to humans, resulting in severe human disease.

Outdoor cats have a bigger risk of contracting worms than indoor cats, but indoor cats are still at risk. There are several ways your cat can end up infested with parasitic worms, including:

  • From birth: Kittens are at risk of contracting worms through their mother, typically from feeding on their mother’s milk after birth.
  • Environmental: Worms pass through the stool of infected animals. If a cat comes in contact with infected stools, soil, or contaminated grass, food, or water, they risk becoming infected with worms.
  • Prey: Because rabbits, rodents, and other small prey can be hosts for parasitic worms, cats who hunt wildlife are at a greater risk of developing parasitic worm infections. Additionally, slugs and snails are prone to lungworm, and cats eating these creatures may become infected.
  • Fleas: Certain pests, such as fleas, are known carriers of certain types of worms, such as tapeworms.
  • Food: Undercooked or raw meat can be contaminated with tapeworm. 

Failure to properly treat and deworm your cat can lead to severe risks, such as intestinal blockages, blockage of the heart’s blood flow, inflamed arteries, and death.

The first symptoms you may notice are diarrhea and gastrointestinal tract distress. These symptoms should bring you to your veterinarian, who will perform fecal testing to diagnose the worm properly. You must receive a proper diagnosis to determine which worm is affecting your cat, as different worms will respond to different treatments. 

You can ask your veterinarian for two types of tests: an ova & parasites fecal exam, which is good at identifying giardia, coccidia, and other worms, or a fecal PCR test, which is more extensive and will provide you with information regarding bacterial infections, viruses, and more. Either test will require you to bring in a small stool sample. Your vet will send the sample to a laboratory for evaluation.

Are you wondering how to get rid of intestinal worms in cats or how to deworm cats?

If you suspect your cat or kitten has worms, they should be treated immediately with deworming products. Kittens are prone to developing severe consequences if the worms are left untreated, so it’s important to treat them as soon as you suspect a worm infestation. Luckily, treatment is very effective in kittens as long as the right medication and dose are given. 

There are several worming products on the market, and they vary between countries. Some worming products are available over the counter (OTC), while others require a veterinarian prescription. OTC medications are less effective than their prescription counterparts, so it’s important to seek veterinarian care. Factors to consider when seeking care include the type of worm, your cat’s age and weight, and other medical history.

If you receive a prescription from your vet, follow the directions carefully. Reinfection is common, so cat worm prevention is necessary. Be sure to practice good sanitation, including removing feces, cleaning the litter box with cat-friendly disinfectants, and avoiding situations such as an overcrowded environment, a diet of raw meats, and an environment filled with fleas, ticks, and rodents. 

How Often Do Cats Need Dewormed?

How often you deworm your cat will depend on its age, environment, and how often it’s allowed outside, in contact with wildlife and bigger communities of cats. 

Adult cats exposed to outdoor environments should be dewormed at least once every three months, though once a month is recommended, especially if they spend a lot of time outdoors. 

Indoor cats with access to wildlife or allowed outdoors at intervals should also be dewormed at least once every three months. 

If your cat spends time in large groups, it may need a more regular deworming regime. 

Because kittens are more prone to some types of worms, such as roundworms, deworming should be started as soon as possible. 3-week-old kittens should be treated every two weeks until they are eight weeks old and then monthly until six months old.