Internal Parasites in Cats


Internal Parasites in Cats

Cats can suffer from various species of internal parasites which are commonly referred to as worms. A cat harboring a considerable number of worm populations in the intestines may show a variety of symptoms of the infection however there are many worm infestations that can go undetected. Cat owners should know how to protect their cats from parasites because people can also get infected particularly with roundworms from their pets.

Common Internal Parasites in Cats


Roundworms are often considered the most common internal parasites affecting cats. Adults can reach 3-5 inches long. A huge population of roundworms has been known to cause obstruction of a cat’s digestive tract. There are several ways worms can be transmitted from one cat to the next. First, nursing kittens may get the parasite from an infected mother’s milk. On the other hand, adult cats can become infected by ingesting the feces of a cat which is harboring roundworms or by eating an infected rodent.


Hookworms are less than an inch long and feed primarily on an animal’s blood, causing life-threatening anemia, especially in very young kittens. Cats can get infected by hookworms either through skin contact or ingestion of infected material.


As the name implies, tapeworms are segmented parasites. Adults can grow to 4-28 inches in length. Cats get the parasite by ingesting infected fleas or rodents which are considered the most common intermediate hosts of tapeworms. Infected cats may suffer from bouts of vomiting accompanied by noticeable loss of weight. Tapeworm segments which are white in color and appear like grains of rice are often seen on the fur around the hind end of infected cats.


Cats with lungworms often fail to show outward signs of the infection while a few develop a cough. Ingestion of intermediate hosts such as snails and slugs and eating a rodent or a bird that has ingested an intermediate host are the most common routes of infection of lungworms in cats.

Except for lungworms that reside in the lungs, roundworms, tapeworms, and hookworms inhabit the intestines of the cat.

General Signs of Parasite Infestation in Cats

Parasite infestation in cats is often manifested by digestive signs including:

  • • Diarrhea
  • • Vomiting
  • • Constipation
  • • Bloody stool
  • • Weight loss
  • • Pot-bellied appearance
  • • Coughing
  • • Breathing problems
  • • Worms may be visible in stool or tapeworm segments seen near the anus

Outdoor cats and those with frequent exposure to soil where other animals defecate have higher risks of getting the infection.

Diagnosis, prevention and treatment of parasites in cats

Your veterinarian can confirm the presence of internal parasites in cats by conducting a stool exam.

If you think that your cat is harboring parasites, you should not attempt to self-treat because cats are sensitive to certain medications and they should be treated only for the specific species of parasite which is present. After your vet has identified the parasite, he will prescribe the best treatment regimen to get rid of the parasites.

You can protect your cat from getting worms by keeping them indoors to reduce and/or totally avoid exposure with infected cats, feces, and intermediate hosts.