Tapeworms in Cats: Signs, Causes and How to Prevent Them

What tapeworms are and how cats catch them

The tapeworm owners see most often in cats is Dipylidium caninum. Its larvae live inside fleas, so a cat becomes infected when it swallows a flea during normal grooming. VCA Animal Hospitals notes that cats cannot catch this tapeworm by eating its eggs directly: the flea is the necessary middle step. That is why a cat with tapeworms almost always has, or recently had, fleas, even if you have never seen one.

A second group, the Taenia tapeworms, uses mice, rats, rabbits and birds as the in-between host. Cats that hunt catch them by eating infected prey. Less often, cats can carry Echinococcus, a tapeworm that matters mainly because it can harm people. An adult tapeworm attaches to the wall of the small intestine and can grow to around 11 inches, shedding egg-filled segments from its tail end.

Signs of tapeworms in cats

Many cats with tapeworms look and act completely normal. The giveaway is the segments. Fresh ones are creamy white, about the size of a grain of rice or a cucumber seed, and may move slightly. Once they dry they shrink, turn yellowish and look like sesame seeds or dry rice stuck to the fur around the anus, on bedding, or on the surface of stool in the litter box.

Other signs are less common. A cat may lick or groom under the tail more than usual, and occasionally a cat vomits a whole worm, which looks like a flat white strand. The Merck Veterinary Manual lists poor coat, variable appetite and mild diarrhea as possible signs, and heavy infections can rarely cause weight loss, especially in kittens or cats that are already unwell. Scooting is far more common in dogs than in cats.

When to call your vet today

Tapeworms on their own are not an emergency, but book an appointment soon whenever you see segments, because the medicines that work best are prescription products and your vet will want to rule out other worms at the same time. Call the same day if your cat is also losing weight, has repeated vomiting, has diarrhea lasting more than a day or two, or seems quiet and off food.

Kittens deserve faster attention. A kitten with worms of any kind, a potbelly, a dull coat, diarrhea or poor growth should be seen promptly, since young cats have little reserve and often carry more than one type of parasite. Also call if you see worms that look like spaghetti strands rather than flat segments, because those are more likely roundworms, which need different treatment.

When it's an emergency

Tapeworms very rarely cause an emergency in an adult cat. Go to your vet or the nearest emergency vet straight away if your cat has repeated vomiting and cannot keep water down, has a swollen, painful belly, is weak or collapsing, has pale gums, or has black, tarry or bloody stool. Those signs point to a more serious problem than tapeworms and need to be checked the same day.

The same applies to a young kitten that stops nursing or eating, becomes cold or limp, or has severe diarrhea. Small kittens can dehydrate within hours, so do not wait to see whether it passes. If you are unsure, phone your vet or an emergency clinic and describe what you are seeing; they can tell you how quickly to come in.

What you can safely do at home

Do not give over-the-counter or leftover dewormers, or any human medicine, without your vet's say-so. Products differ in which worms they kill, and the wrong one can leave the tapeworm in place while costing you time. What you can do is collect evidence: put a few segments in a sealed bag or a small container, or take a clear photo, and bring them to the appointment. Note when you first saw them and whether your cat hunts or goes outdoors.

Start working on fleas, because treating the worm without treating fleas usually means the tapeworm is back within weeks. Wash your cat's bedding in hot water, vacuum carpets and furniture thoroughly, and empty the vacuum outside. Ask your vet which flea product suits your cat. Treat every pet in the home, not just the one with segments.

What the vet will likely check

Tapeworms are usually diagnosed by seeing the segments, because their eggs are packed inside the segments and often do not show up on a routine fecal test. Your vet will look at the sample or photo you bring, check your cat's coat and skin for fleas or flea dirt, and examine the belly, weight and overall body condition. A fecal test may still be run to look for roundworms, hookworms or other parasites at the same visit.

Treatment is a prescription dewormer given by mouth, applied to the skin or injected. These drugs dissolve the worm inside the gut, so you usually will not see it passed afterward. VCA describes the outlook as excellent. Your vet will pair it with a flea-control plan and may suggest regular deworming for cats that hunt, since a cat that keeps catching prey will keep picking up Taenia tapeworms.

Prevention and the risk to people

Year-round flea control is the single most effective way to prevent the common tapeworm, and Merck stresses that it matters even for indoor cats, because fleas ride in on people, dogs and visitors. Keeping cats indoors or limiting hunting reduces Taenia infections, and scooping the litter box daily keeps the environment cleaner. Regular checkups give your vet a chance to adjust parasite prevention to how your cat actually lives.

People rarely catch Dipylidium, and only by swallowing an infected flea, which has mostly been reported in young children. Good flea control and handwashing after handling litter make that very unlikely. Echinococcus is more serious for humans but uncommon in cats; hygiene and rodent control help. If anyone in your home is pregnant, very young or has a weakened immune system, mention it to your vet and your own doctor.

This page is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your pet.