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How to Tell if My Cat Has Worms? 5 Vet-Reviewed Signs

Written by: Christian Adams

Last Updated on March 8, 2024 by Catster Editorial Team

cat owner belly rubbing her cat

How to Tell if My Cat Has Worms? 5 Vet-Reviewed Signs


Dr. Tabitha Henson (Vet) Photo


Dr. Tabitha Henson (Vet)

The information is current and up-to-date in accordance with the latest veterinarian research.

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Parasitic worms are repulsive to think about, but they’re a common health problem for cats. Along with being off-putting, worms can cause severe complications for your cat if left untreated.

Fortunately, worms can be treated safely and effectively in cats, and there are numerous ways to prevent future recurrences. Worm infestations can be asymptomatic or severe, but the signs are clear if you know what to look for. Here are some likely signs your cat has worms.

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How to Tell If Your Cat Has Worms

1. Vomiting and Diarrhea

One of the most obvious signs of worms is vomiting or diarrhea. Intestinal worms get nourishment from the food in the digestive tract, causing damage and inflammation to the walls of the intestines. This can lead to vomiting and diarrhea.

Some worms, like hookworms, attach to the intestinal wall and feed on blood, leading to internal hemorrhaging and bloody diarrhea. They are less common but may still be present in cats.

Cat vomiting
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 2. Mucus or Worm Parts in Stool

When your cat has worms, the intestines secrete mucus to defend against the parasitic invasion. This causes your cat’s stool to look slimy from the excess mucus. The segments or parts of the worms may break apart and show up in your cat’s stool as well.

3. Lethargy

As mentioned, worms are parasites and rob your cat of nutrients. As a result, your cat may become malnourished or anemic if the infestation goes on long enough. Without proper nutrition, your cat may become lethargic or fatigued more quickly than a healthy cat.

Ragamuffin cat lying in a cat bed
Image Credit by: Ryo Nagashima, Shutterstock

4. Dull Coat

Also related to nutrition, a cat with worms will have a dull coat and dry skin. Nutritional deficiencies often show in the health of the coat and skin. Worms consume vital nutrients your cat needs to maintain a healthy, shiny coat and well-moisturized skin, leading to a dull appearance and dry skin.

5. Appetite Problems

Cats with worms may have finicky appetites. They may become hungry from the nutritional deficiencies caused by the worms, eating more to make up the difference. Conversely, cats may refuse food at other times because of digestive upset or pain, leading to weight loss.

persian cat eating dry food
Image Credit by: Patrick Foto, Shutterstock

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Are Worms in Cats Dangerous?

Worms are naturally found in the digestive systems of many animals. As long as they are in small numbers, they don’t cause harm. When the parasite load becomes excessive, it can cause health and nutritional problems for your cat. It can be serious in any cat, but it’s more significant in kittens who are in development.

Worms steal vital nutrients, leading to stunted growth, dehydration, anemia, and malnutrition. This can also happen with worms that feed on blood, leading to severe anemia. Worms may rob your cat of vital nutrients directly from feeding off the food in the digestive tract and indirectly through diarrhea and vomiting. It’s like your cat is starving despite consuming plenty of healthy food.

grey cat eating food
Image Credit by: Pixel-Shot, Shutterstock

Can the Symptoms Be Caused by Something Else?

Though these symptoms are signs of a worm infestation, they can be related to many other health problems. Diarrhea, for example, could be caused by something as innocuous as food that didn’t agree with your cat or as severe as toxicity from chemicals or poisonous plants. Other potential causes include bacteria, viruses, food intolerances, and allergies.

It’s vital to take your cat to the vet for any prolonged signs. An occasional bout of diarrhea or vomiting may be nothing to worry about, but if it continues, it warrants a vet visit. This is also true of other signs, such as fatigue or inappetence, which could be an off day or indicate something more insidious.

cat examined by Vets
Image Credit by: Kzenon, Shutterstock

How to Prevent Worms in Cats

Worm infestations in cats can be prevented through good hygiene and year-round use of heartworm, intestinal worm, and parasite prevention. Yearly fecal exams at the vet can also help monitor for intestinal worms. You should always spot-clean the litter box daily, change out the litter, and disinfect the litter box at least once a month. This helps prevent exposure to contaminated feces.

If your cat spends time outdoors sometimes, you can remove their solid waste from the yard or flower beds to minimize exposure to parasites. Whether you have an indoor, outdoor, or indoor/outdoor feline, they need regular vet visits. Some worms and other parasites can be asymptomatic until the infestation is severe, but your vet can help you identify problems early on.

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Worms are common in cats, but they shouldn’t be ignored. Left untreated, they can cause severe problems for your cats, including malnutrition and anemia. In addition, many of the signs of worms could also be caused by other health conditions, some of which are serious. Always schedule a checkup for your cat if you notice concerning signs, and commit to regular wellness exams as part of your preventative healthcare plan.

Featured Image Credit by: Anna Hoychuk, Shutterstock

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