How to Tell If Cat Has Worms: Recognizing the Silent Invaders in Your Feline Friend
I've been around cats for the better part of three decades, and if there's one thing that still catches pet owners off guard, it's discovering their perfectly healthy-looking cat is harboring a belly full of parasites. The thing about worms is they're sneaky little devils – your cat can be hosting an entire ecosystem of parasites while still maintaining that aloof, dignified demeanor we all know and love.
Let me paint you a picture that might sound familiar. You're going about your day, maybe scooping the litter box (everyone's favorite chore), when you notice something... off. Maybe it's a weird rice-like grain stuck to your cat's fur near their rear end. Or perhaps Mittens has been eating like a horse but somehow looks thinner. These moments – these little "huh, that's weird" observations – are often your first real clue that something parasitic might be going on.
The Usual Suspects: Common Worms That Plague Our Feline Companions
Before we dive into the detective work of spotting worms, let's talk about what we're actually dealing with here. In my years of cat ownership and countless vet visits (both routine and emergency), I've learned that not all worms are created equal.
Roundworms are probably the most common culprits. These spaghetti-like parasites are particularly fond of kittens, though adult cats aren't immune. I remember the first time I saw one – it was in a foster kitten's vomit, and I nearly jumped out of my skin. They're surprisingly large when you see them outside of a textbook illustration.
Then there are tapeworms, which honestly look nothing like what you'd expect from the name. They're flat, segmented creatures that break apart like perforated paper. The segments you'll most likely encounter look like tiny grains of rice or sesame seeds. They have this disturbing habit of crawling out of your cat's rear end while still moving, which is exactly as horrifying as it sounds.
Hookworms and whipworms round out the rogues' gallery, though they're less common in cats than in dogs. These microscopic troublemakers are virtually invisible to the naked eye, making them particularly insidious. You won't see them crawling around – you'll only see the damage they leave behind.
The Tell-Tale Signs: When Your Cat's Body Starts Dropping Hints
Now, cats are masters at hiding illness. It's an evolutionary trait that served them well in the wild but drives us modern cat parents absolutely bonkers. However, worms have a way of making their presence known, even in the most stoic feline.
The most obvious sign – and I mean knock-you-over-the-head obvious – is actually seeing worms. This might happen in vomit (sorry if you're eating while reading this), in feces, or those aforementioned tapeworm segments around your cat's bottom or in their bedding. I once had a cat who left tapeworm segments on my pillow. Nothing quite wakes you up like parasites on your pillowcase.
But visual confirmation is actually relatively rare. More often, you'll notice behavioral and physical changes that seem unconnected until you put the pieces together. A cat with worms might develop a voracious appetite yet somehow lose weight. It's like they're feeding an army – because, well, they are. The parasites are literally stealing nutrients from your cat's digestive system.
The condition of your cat's coat can tell you volumes. A healthy cat should have a glossy, smooth coat. A cat with worms often develops a dull, rough coat that feels different to the touch. I've noticed this change is gradual – you might not notice it day to day, but then one day you're petting your cat and think, "When did their fur get so... blah?"
Digestive upset is another red flag, though it's tricky because cats can have sensitive stomachs for a million reasons. But persistent diarrhea, especially if it's accompanied by blood or mucus, warrants investigation. Some cats with worms also develop a pot-bellied appearance, particularly kittens with heavy roundworm infestations. It's a distinctly round, firm belly that looks out of proportion to the rest of their body.
The Behavioral Clues That Something's Amiss
Beyond the physical symptoms, worms can cause some pretty specific behavioral changes. The infamous "butt scooting" is a classic sign of tapeworms. If your cat is dragging their rear end across your carpet like they're trying to start a very small fire, they're probably dealing with the irritation caused by tapeworm segments.
Lethargy is another big one, though admittedly, distinguishing between a lethargic cat and a cat just being a cat can be challenging. We're talking about animals that sleep 16 hours a day on a good day. But there's a difference between normal cat laziness and the exhaustion that comes from fighting off parasites. A worm-infested cat might seem less interested in play, more reluctant to jump or climb, or just generally less engaged with their environment.
I've also noticed that cats with worms sometimes develop weird eating habits. They might become obsessed with food, crying for meals constantly, or conversely, they might lose interest in eating altogether. One of my cats developed a habit of eating grass obsessively when she had tapeworms – apparently, some cats instinctively try to self-medicate.
The Less Obvious Signs That Often Get Missed
Here's where my years of cat ownership have taught me to look beyond the textbook symptoms. Cats with worms sometimes develop a peculiar sweet smell to their breath. It's not exactly pleasant – more like overripe fruit. I've also noticed that some cats with worms seem to have trouble with their third eyelid, that translucent membrane in the corner of their eye. It might be more visible than usual or seem inflamed.
Another subtle sign is changes in grooming habits. Cats are fastidious groomers, but a cat dealing with worms might either over-groom (especially around their rear end) or under-groom because they feel unwell. You might notice mats forming in their fur or areas they're licking bald.
The quality of your cat's meow can even change. This sounds crazy, I know, but I've had cats whose voices became raspier or weaker when they were dealing with parasites. It's like the overall toll on their system affects everything, right down to their vocal cords.
When Kittens Are Involved: Special Considerations
Kittens are particularly vulnerable to worms, and the signs can be more dramatic. I've fostered enough litters to know that a kitten with worms is a whole different ballgame than an adult cat with the same problem.
Kittens with worms often fail to thrive. They might be smaller than their littermates, have trouble nursing, or seem generally weaker. The pot-bellied appearance is much more pronounced in kittens, and they can develop severe anemia from hookworms frighteningly quickly.
One thing that always breaks my heart is seeing a kitten with worms try to play. They want to – you can see it in their eyes – but they just don't have the energy. They'll start to pounce, then sort of give up halfway through, like someone pulled their batteries out.
The Inspection Process: Getting Up Close and Personal
Okay, let's talk about the unglamorous but necessary task of actually checking your cat for worms. This isn't anyone's idea of a good time, but it's important.
First, the litter box inspection. Yes, you need to look at your cat's poop. Fresh feces might contain visible worms, but more often, you're looking for those rice-like tapeworm segments. They're usually around the outside of the feces rather than mixed in. Pro tip: use a popsicle stick or disposable utensil to poke around if you need a closer look. There's no shame in the game when it comes to your cat's health.
Checking your cat's rear end requires a bit more finesse. Tapeworm segments often stick to the fur around the anus and can look like dried rice grains. They might also be in your cat's bedding or anywhere they've been sitting. I once found a collection of them on my couch cushion – not exactly what you want to discover during movie night.
For a really thorough check, you might need to part the fur around your cat's anus. I know, I know – neither you nor your cat will enjoy this. But sometimes those segments hide in the fur, and you need to look closely. Having a helper to hold the cat while you investigate can make this process slightly less traumatic for everyone involved.
The Vet Visit: When Home Detective Work Isn't Enough
Sometimes, despite all your careful observation, you just can't tell for sure if your cat has worms. That's where your vet comes in. They have tools and tests that go way beyond what we can do at home.
The standard test is a fecal examination, where they look at a poop sample under a microscope. This can identify worm eggs that are invisible to the naked eye. Fair warning: collecting a fecal sample from a cat is an adventure in itself. I recommend keeping a clean litter box handy and pouncing (metaphorically) as soon as your cat makes a deposit.
Some vets might also recommend blood tests, especially if they suspect hookworms, which can cause anemia. The blood test can show if your cat's red blood cell count is low, which might indicate a parasitic infection.
Prevention: Because an Ounce of It Really Is Worth a Pound of Cure
After dealing with worms in multiple cats over the years, I've become somewhat evangelical about prevention. It's so much easier to prevent worms than to treat them, both for you and your cat.
Indoor cats aren't immune, despite what many people think. Worms can come in on your shoes, through insects that make their way inside, or even through potting soil if you have houseplants. I learned this the hard way when my strictly indoor cat developed tapeworms – turns out, she'd been snacking on the occasional flea that hitched a ride inside on my dog.
Regular deworming is key, but the schedule depends on your cat's lifestyle. Outdoor cats or those who hunt need more frequent treatment. Even indoor cats benefit from periodic deworming, especially if you have other pets or if your cat has a history of worm infections.
Flea control is absolutely crucial since fleas are the intermediate host for tapeworms. A cat can't get tapeworms without ingesting an infected flea, so keeping fleas at bay is like closing one of the main highways for worm transmission.
The Treatment Journey: What to Expect
If your cat does have worms, treatment is usually straightforward but requires some patience. Deworming medications come in various forms – pills, liquids, topical treatments, and even injections. Each type of worm requires a specific medication, which is why proper identification is important.
I'll be honest: giving a cat deworming medication can be... challenging. I've tried every pill-giving technique in the book, from the straightforward "open mouth, insert pill" method to hiding it in treats, pill pockets, and even crushing it into wet food (when the medication allows). Every cat is different. My current cat will eat anything if it's mixed with tuna juice. My previous cat could detect a hidden pill from three rooms away.
The thing about deworming is that it often requires multiple rounds. You might need to treat again in two to three weeks to catch any worms that were in larval stage during the first treatment. This is where a lot of people fail – they do one treatment, see improvement, and think they're done. Then the worms come back with a vengeance.
Living with the Reality of Worms
Here's something that might make you feel better: almost every cat will deal with worms at some point in their life. It's not a reflection on your pet parenting skills. It's just part of sharing your life with a small predator who likes to stick their nose in questionable places.
I've learned to be vigilant but not paranoid. Regular vet check-ups, keeping an eye on the litter box, and staying on top of preventive care have served me well. And yes, I've become that person who examines their cat's rear end probably more often than is strictly necessary. But hey, that's love, right?
The most important thing is not to panic if you discover your cat has worms. It's treatable, it's common, and with proper care, your cat will be back to their normal, slightly judgmental self in no time. Just maybe wash your hands a little more often during treatment. And perhaps invest in some rubber gloves for those litter box investigations. Trust me on that one.
Remember, our cats depend on us to notice when something's wrong. They can't tell us they feel sick or that their belly hurts. All they can do is show us through changes in their behavior and body. Learning to read these signs – to really see our cats – is part of the beautiful, sometimes gross, always rewarding journey of cat ownership.
So the next time you're scooping that litter box or notice your cat doing the butt-scoot shuffle across your clean floor, remember: you're not just a pet owner. You're a detective, a nurse, and a guardian all rolled into one. And your cat, whether they show it or not, is lucky to have you looking out for them.
Authoritative Sources:
Bowman, Dwight D. Georgis' Parasitology for Veterinarians. 11th ed., Elsevier, 2021.
Centers for Disease Control and Prevention. "Parasites - Toxocariasis (also known as Roundworm Infection)." CDC.gov, U.S. Department of Health & Human Services, 2020.
Companion Animal Parasite Council. "Intestinal Parasites - Cat Owners." CAPC Vet, 2023.
Cornell University College of Veterinary Medicine. "Gastrointestinal Parasites of Cats." Cornell Feline Health Center, Cornell University, 2021.
Ettinger, Stephen J., and Edward C. Feldman. Textbook of Veterinary Internal Medicine. 8th ed., Elsevier, 2017.
Merck Veterinary Manual. "Gastrointestinal Parasites of Small Animals." Merckvetmanual.com, Merck & Co., Inc., 2022.
Taylor, M.A., R.L. Coop, and R.L. Wall. Veterinary Parasitology. 4th ed., Wiley-Blackwell, 2016.