Worms are very common in cats, and most cats pick up roundworms at some point, often as kittens. Many infected cats look perfectly healthy, while others lose weight, get diarrhea or develop a pot belly. Some worms can also affect people, especially children. Routine deworming, flea control and a few hygiene habits keep the risk low.
Quick answer: The main worms in cats are roundworms, tapeworms and hookworms, with heartworm and lungworm in some areas. Signs include weight loss, diarrhea, vomiting, a bloated belly, a dull coat, and rice-like segments around the bottom, but many cats show no signs. Kittens need deworming from about three weeks old, and adult cats need regular treatment based on their lifestyle. Ask your vet for a cat-safe product and schedule.
Common types of worms in cats
| Worm | How cats get it | What you may notice |
|---|---|---|
| Roundworm | Mother’s milk, eating infected rodents, swallowing eggs from soil or feces | Pot belly in kittens, diarrhea, vomiting, poor growth, spaghetti-like worms in vomit or stool |
| Tapeworm | Swallowing infected fleas while grooming, or eating prey | Rice-like segments around the bottom, in stool or bedding; scooting |
| Hookworm | Larvae through the skin or swallowed while grooming | Anemia, pale gums, weakness, dark tarry stool, especially in kittens |
| Heartworm | Mosquito bites, including indoor cats in risk areas | Coughing, breathing trouble, vomiting, or sometimes no signs |
Signs your cat may have worms
Worm symptoms are often vague, and many cats show none at all, which is why routine treatment matters. Look out for:
- Weight loss despite a good appetite
- Diarrhea, sometimes with mucus or blood; see diarrhea in cats
- Vomiting, sometimes with worms in it; see cat vomiting
- A swollen, pot-bellied look, especially in kittens
- A dull, scruffy coat
- Scooting or licking around the bottom
- Rice-like segments around the tail, in stool or bedding
- Pale gums, weakness or low energy
- Coughing or breathing changes, with heartworm or lungworm
Worms in kittens
Kittens are at the highest risk. Roundworm larvae lying dormant in a mother cat can become active during pregnancy and pass to kittens through her milk. Heavy roundworm burdens can cause poor growth and even blockages, and hookworms can cause dangerous blood loss.
Guidance from the Companion Animal Parasite Council, summarized by Cornell’s Catwatch, recommends that kittens are dewormed starting at about three weeks old, again at around eight and ten weeks, and then monthly until about six months old. Nursing mother cats should be treated alongside their kittens. Your vet will tailor this, so follow their schedule. For more on early health care, see common health problems in kittens.
Urgent: contact a vet promptly if a kitten has pale gums, weakness, black or bloody stool, a very swollen belly, repeated vomiting or diarrhea, or isn’t growing. Kittens can become seriously ill from worms quickly.
Deworming adult cats
How often an adult cat needs deworming depends on its lifestyle. Cats that hunt, go outdoors, or live with fleas need more frequent treatment than strictly indoor cats. Catwatch notes a common recommendation of routine testing and deworming about every three months, and new cats should be dewormed soon after arriving. Some monthly parasite products cover several types of worms as well as fleas, and in areas where heartworm is present, vets often recommend year-round prevention, as there is no approved treatment for heartworm in cats.
Use only products recommended by your vet and licensed for cats, at the right dose for your cat’s current weight. Products for dogs, or medicines bought without advice, may not work or could be harmful.
The flea and tapeworm link
The most common tapeworm in cats is spread by fleas. When a cat grooms and swallows an infected flea, the tapeworm develops in its gut. That means treating tapeworm without controlling fleas often leads straight back to reinfection. Keep flea treatment up to date for every pet in the home; see fleas and ticks on cats.
Can people catch worms from cats?
Some cat worms, especially roundworms and hookworms, can infect people, usually by accidentally swallowing eggs from soil or contaminated surfaces. Children are most at risk. Simple habits reduce the chance:
- Deworm pets regularly, as your vet advises
- Scoop the litter box daily and wash hands afterward
- Cover children’s sandpits when not in use
- Wear gloves when gardening, and wash hands before eating
Diagnosis and treatment
Your vet may test a stool sample for worm eggs, although some worms don’t always show up, so a negative test doesn’t always rule them out. Tapeworm is often spotted by the segments around the bottom. Heartworm needs blood tests and sometimes imaging. Treatment uses deworming medicines suited to the worm type, and sometimes repeat doses. Cats that are weak or anemic may need extra care.
If your cat seems uncomfortable, isn’t eating or is losing weight, see signs your cat is sick and signs your cat is in pain. Keep vaccinations up to date too; see the cat vaccination schedule.
Frequently asked questions
Do indoor cats need deworming?
Often yes, though usually less often than outdoor cats. Indoor cats can still get worms from fleas, insects, mosquitoes or eggs carried in on shoes. Your vet can recommend a schedule based on your cat’s lifestyle.
What do worms in cat poop look like?
Roundworms look like strands of spaghetti. Tapeworm segments look like small grains of rice and may move when fresh. Hookworms are usually too small to see. Many infections show no visible worms at all.
How often should I deworm my kitten?
Kittens usually start deworming at about three weeks old, with repeat treatments at around eight and ten weeks and then monthly until about six months. Follow your vet’s schedule, as it may vary with your kitten’s health and history.
Can I catch worms from my cat?
Some cat worms, such as roundworms and hookworms, can infect people, usually through eggs in soil or on contaminated hands. Regular deworming, daily litter scooping and hand washing keep the risk low.
