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

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	Dr. Tabitha Henson (Vet) Photo

Reviewed & Fact-Checked By

Dr. Tabitha Henson (Vet)

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

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Worms are gross to think about, but they’re a common health problem for cats. Along with being off-putting, worms can cause serious 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 symptoms 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 leads to symptoms of digestive upset like vomiting and diarrhea.

Some types of 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.

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 2. Mucus or Worm Parts in Stool

When your cat has worms, the intestines will 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.

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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.

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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 take many of the vital nutrients your cat needs to maintain a healthy, shiny coat and well-moisturized skin, leading to a dull appearance and dry skin.

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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 also refuse food at other times because of digestive upset or pain, leading to weight loss.

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Are Worms in Cats Dangerous?

Worms are found in the digestive systems of many animals naturally. As long as they are in small numbers, they don’t cause harm. When the parasite load becomes excessive, they can cause health and nutritional problems for the host—your cat.

This can be serious in any cat, but it’s more significant in kittens who are in development. Worms can 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 not only rob your cat of vital nutrients directly, from feeding off the food in the digestive tract but indirectly through symptoms like diarrhea and vomiting. Essentially, it’s like your cat is starving, despite plenty of healthy food.

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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 serious as toxicity from chemicals or poisonous plants. Other potential causes include bacteria, viruses, food intolerances, and allergies.

It’s important to take your cat to the vet for any prolonged symptoms. 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 symptoms, such as fatigue or inappetence, which could be an off day or could indicate something more insidious.

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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 and change out the litter and disinfect the litter box at least once a month. This helps to prevent exposure to contaminated stool.

If your cats are outdoors some of the time, scoop stool from the yard or flower beds to minimize exposure to parasites.

Whether your cats are indoor, outdoor, or indoor/outdoor, they need regular vet visits. Some worms and other parasites can be asymptomatic—or don’t show symptoms 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 serious problems for your cats, including malnutrition and anemia. In addition, many of the symptoms of worms could also be caused by other health conditions, some of which are serious. Always schedule a checkup for your cat if you see possible symptoms and commit to regular wellness exams as part of your preventative healthcare plan.

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Featured Image Credit: Anna Hoychuk, Shutterstock