How can you tell if your cat has worms? By: Rene
How can you tell if your cat has worms? By: Rene

While many people think of worms as a condition that typically only affects kittens, cats of any age can get worms. This is true whether your cats live indoors, go outside sometimes or stay outside all the time.

Several types of worms can affect cats, and although some of the symptoms are different according to the type of worm, they all share some symptoms.

If your cat has symptoms of worms, you’ll need to take the cat to your veterinarian to determine which type of worm is present, and therefore which treatment is appropriate. For the purposes of this article, we’ll take a look at 4 common types of worms in cats.


1. Roundworms

Roundworms, known as Toxascaris leonine or Toxocara cati, are a type of parasite that commonly infests cats — and yes, they can be spread to humans.

Roundworms may be anywhere from 2 to 4 inches long. They are light in color, typically tan or white, and their ends are tapered. If you see what appear to be strands of spaghetti in your cat’s stool or in vomit, it is likely an infestation of roundworms.

How do I know if my cat has roundworms? Check for 1 or more of the following symptoms:

  • A very full or pot-bellied appearance that occurs in a short amount of time
  • Regular vomiting
  • Frequent loose stools or diarrhea
  • A decrease in energy or activity
Roundworms inside a cat's small intestine.
Roundworms inside a cat’s small intestine.

Kittens will sometimes get roundworms when they are nursing as a result of roundworm larvae in the mammary glands of their mother. A cat of any age can get roundworms by swallowing the eggs containing larvae; the cat typically eats the host containing the eggs. Common roundworm hosts include birds, rodents, roaches and earthworms.

Roundworms can be treated using a deworming product prescribed by your cat’s veterinarian.

2. Tapeworms

Tapeworms, or Dipylidium caninum, are another type of worm commonly found in cats. Fleas carry tapeworms, so infestation from tapeworms is typically a side effect of a flea infestation.

Tapeworms are quite visible, and appear in the cat’s stool or in the fur surrounding its tail. Segments of the tapeworm break off and pass through the cat’s stool, and these have a small, rice-like appearance. Inside the body, a tapeworm can grow several inches long.

How do I know if my cat has tapeworms? Symptoms of an infestation include:

  • Weight loss — minor to severe
  • The appearance of tapeworm segments in stool or attached to the cat’s tail or fur around its anus

As mentioned above, cats get tapeworms from fleas. Young fleas, or larvae, eat tapeworm eggs and then grow into adults. If your cat ends up swallowing the flea when licking at flea bites or chewing on the skin, the tapeworm exits the flea and attaches itself to your cat’s intestinal lining, where it grows.

Tiny segments detach from the tapeworm and are released in your cat’s stool; a cat may vomit up a larger portion of the tapeworm on occasion.

Tapeworms can be treated using a deworming product prescribed by your vet; however, since fleas carry tapeworms, adult fleas, larvae and eggs should also be killed and your pet’s bedding should be treated to prevent another occurrence.

In the video below, Greg Martinez, DVM, explains more:

3. Hookworms

Hookworms, or Ancylostoma braziliense, are not visible to the human eye, unlike most other types of parasites. They are thin and grow to about 1/8-inch long.

Hookworms can be transmitted from cats to humans if they walk in an infested area with bare feet; the hookworms can burrow into the skin of the feet and enter the digestive tract. They feed on the blood of the cat, which can cause anemia. This is especially dangerous for kittens because anemia in a small animal can cause death.


How do I know if my cat has hookworms? Most adult cats will not exhibit symptoms from hookworms because they become immune to them, but kittens may exhibit the following symptoms:

  • Blood appearing in the kitten’s stool
  • Frequent loose stool or diarrhea
  • Pain in the abdomen
  • Weakness or lethargy

A cat typically gets hookworms from eggs found in stool on the ground, as a hookworm will lay hundreds of eggs that will then pass to the stool. The hookworm larvae, once hatched, will remain in the stool for weeks. If the cat steps in the infected stool, the hookworm larvae may stick to the cat’s feet; grooming of the feet will allow the hookworm to enter through the mouth of the cat, where it will travel to the intestines. Hookworms can also burrow into a cat’s skin and then proceed to the intestine.

After only 2 to 3 weeks, the larvae are mature enough to produce eggs of their own, producing more larvae. Kittens can also get hookworms from nursing if the mother’s milk is infected with hookworms.

Hookworms can be treated with a deworming product prescribed by a veterinarian; 2 or more treatments may be necessary to kill the adult hookworms and the larvae after they hatch.

4. Stomach Worms

Stomach worms, known as Physaloptera or Ollanulus tricuspis, are a less common type of parasite that infects cats. Most infestations occur as a result of a cat eating the vomit of an infected animal.

How do I know if my cat has stomach worms? These parasites are small, typically less than half an inch in length, and are not usually visible externally in a cat’s stool. Symptoms include:

  • Moderate to severe vomiting
  • Rapid weight loss
  • Decrease in activity or lethargy

Ollulanus tricuspis infections are rarely seen in the United States, but infestations can occur when a large number of cats are housed in a single area. Physaloptera infestations are more common, and result from a cat either eating the vomit of another infected cat or eating a host for the parasite.

Common hosts for stomach worms include rodents, cockroaches, crickets, beetles and grubs. Stomach worms can be treated using a deworming product prescribed by your veterinarian. As the worms die, they will pass through your cat’s stool, as will the eggs killed by the treatment. Within 2 weeks, symptoms should subside.

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Leave a Comment

  • Claire

    I collected my cat from
    The cattery after returning from holiday on Saturday. Since then he is always hungry – clearing his bowl every time. He is also tired and sleepy all the time where as he used to be a very energetic cat.
    I found a white thing on the floor which looked like a strand from
    A ready made salad however we don’t keep any chilled good at the moment as we have no fridge.
    I didn’t think anything of it at the time until seeing the pictures on the internet it was about 1.5inches long. I can’t get to the vet until next Wednesday and I’m worried if left this will cause a major issue either with my cat or my son.

  • Guitargirl

    My cat won’t eat or drink. He’s an indoor cat but goes outside at leas three times a day. What’s wrong with him..

    • catfan555

      If your cat won’t eat or drink its a serious problem, take him or her to a vet ASAP. They could have ingested something and have an obstruction.

  • sick kitty

    My kittens fur looks very greasy and unkept. His stomach seems to be swollen but his bones are very visible from weight loss. He has been drinking plenty of water and eating but directly after eating he gets very weak to the point that holding his head up seems to be difficult. The mother of the kittens was a stray cat that delivered the five kittend in our barn. She too had a similiar appearance as the sick kitten and died when they were still young. I have never had a cat and thought her appearance was from being a young cat and giving birth to five little ones. I didnt know she was sick. I am a single mother with five children and do not have the funds to take this kitten to a vet and the humane society wants $35 if they take the kitten even though they arent actually mine. Since the stray cat delivered them in my barn and since I had fed them to keep them from dieing they said they became my responsibility. I wouldnt mind to pay whatever is necessary to a vet to help this kitten, but I just dont have it not even $35 for the humane society. I was hoping that by his symptoms you might have an idea as to what it might be and could tell me what if anything that I may be able to do on my own to help this poor kitten. I have checked the kitten over pretty good and there is no signs of worms of any type that are visible as far as I can tell.
    Please help me before something happens to him. Thank you

    • Pets Adviser

      Hi, unfortunately we cannot offer any sort of diagnosis. This sounds like an urgent medical issue, in which case the kitten needs to see a vet as soon as possible. It’s hard to say for sure what’s going on. You can email us and we will try to find someone in the area who can take the kitten(s):

    • ErinK625

      Do you have a Petco near you? I know you posted this 2month’s ago… But Petco has services (dewormer & vaccines) every other Saturday done by a vet & if there’s something really wrong (besides worms) they’ll be able to tell you & you won’t be charged.. I think the dewormer is $15… However based on the appearance you described it sounds like the kitten has anemia…

    • Steve

      I feel sorry for your kids…

  • Kristin

    My cat developed runny stools in the last couple of days. About 1-2 runny/wet stools per day. He is two years old and just recently going outside. He doesn’t seem sick in any other way, so I’m not sure if I should take him to the vet.

  • Gabrielle

    My cat was just cleaning himself in his private parts and something flew off, i thought maybe it was dirt but when i looked at it it was a white little worm about a centimeter long and its alive, does anybody know what this is?!

    • Sweet Momma

      did u find out what this was?

  • Ashley&Meow Abel

    My cat, who is 1 & 1/2 years old, usually can’t wait for her meals and scarffs everything up. But lately she has had a light appetite. She’s still grazing every so often but hasn’t finished her morning meal yet and it’s almost time for her usual evening meal time… Anyone else experience this? She also seems very needy. Always climbing into our laps. Looking up at us and meowing. Stuff like that. She’s still playful and what not, but were not sure what’s going on abd done have finances to get her to the vet. Any advice?

    • Jamie Johnson

      i feel your pain. Our cat Maceo does the same thing. She constantly is crying when my husband leaves in the morning, and drags this sad little blue teddy bear around. she is ALWAYS on us, mostly my husband, who originally rescued her. She became my baby when we got married 6 yrs ago, But she is SO needy now. And she sleeps all day. she only wakes up when my husband comes home from wk 8 hrs later. she cries non stop when he is gone. she scarfs and barfs sometimes, and this morning, i found what i think may be worms in her stool. so gross, and so scary. we, too, don’t have any money to take her anywhere. i don’t know why they have free clinics for people and not animals. oh, and she also is constantly scratching at her ear, which she’s had problems with before. i am so scared. she HATES going to the vet, and it’s almost impossible to get her there. she SCREAMS and cries the whole car ride. we drive like we are in the indy 500 just to get her there. I don’t know what’s wrong with her, but it’s something. i love my cat like a child, as I have no children and lost my mother when i was only 20. i have no one to talk to about it because no one cares about cats, only dogs. i hope your cat gets better, and I pray mine does, too. When i know more, i’ll post more.

      Sincerely scared,
      Maceo’s momma

  • rachael

    My cat lives indoors she is fed well a mixture of wet and dry food, but she is now 1 year old and is tiny and looks thin i have checked her stools and can’t see anything she is happt enough but im just a bit concerned with her size …any one got any ideas

    • David Deleon Baker

      Some cats are naturally small. My own cat, Hillary, has always been very skinny. The vet says there’s nothing wrong and that’s just the way she is. Of course, that’s my cat and not yours. You should ask your veterinarian about this. That’s the only way to know for sure what’s going on. If you have noticed *a change* in your cat from larger to very small, then that would obviously be a sign of trouble.

  • Ariana

    I was laying in bed and noticed what looked like an over cooked piece of spaghetti (maybe only an inch long) sticking out of my kittens rear end. I have taken her to the vet twice in the three months that I’ve owned her and both times they have tested her for worms and she’s come back negative. It’s possible that I’m overreacting since I have a very prominent phobia of parasites, but is it possible for an indoor kitten (who is the only pet in the house besides my rommate’s snake) to spontaneously get worms? She has fleas but they’re under control (she had them from the moment I bought her; the vet knows of this already) and there are no rodent droppings for her to eat. Money is tight at the moment, but I do plan on calling the vet and asking about getting her tested for parasites again.

  • Poby

    My cat is 4 months old. I took her for deworming 3 times already (the standard kitten dewormer) and treated her fleas problem, but I still see live worms in her bedding. Sometimes small thin white worms, sometimes small thin black. What could it be? Should I take her back for a 4th deworming? Please help. Thanks!

  • alex

    My cat doesn’t have any of these symptoms but she was hanging out with me getting pets and she put her hind end in my face and there was a wiggly little (ALIVE) white thing! I really hope its not worms or something worse, and I hope my other cats don’t get it!:(

    • David Deleon Baker

      Sure sounds like worms. You should see a vet to get the diagnosis and treatment. Good luck.

  • Em

    We got our kitten at 8 weeks old at the end of November. We named her Elsa. She is quite the little chubster and has a ravenous appetite. She even tries to get at our people food. I brought her into the vet for her check up and he was a little concerned about her distended potbelly. It is quite cute actually but definitely something to be alarmed about. Dropped off her stool sample today and am waiting to hear back!

  • joshua

    I have to get my cat checked out idk what kind it is or anything I just found him in the cold in the country. He is the nicest cat ever not one ounce of mean in him my other cat doesn’t like him but he just lays there and pures even with his hissing. But he is very skinny but at the same time has a very bloated tummy do you think it’s worms?

  • Tiff

    i got my cat about a month ago. Today and a few days ago, i found a small white worm-like thing under him when i picked him up. ive only seen two, hes not eating as much but he does eat every couple of hours so i think his eating habits are normal?From other’s post’s it sounds like possibly worms but i plan on taking him to Pet-Co this weekend after calling a vet and see what they say.

  • Max

    My kitten is skinny but eats regularly, I’ve given him an all wormer but he dsnt seem to be putting on weight. Hes energetic like all kittens, sleeps well and is very well loved. I cant figure it out?? Please help!