Tapeworms Are Not Fun

Various pests can infect your pets, both outside on their skin or inside their intestines and other internal organs. Veterinarians recommend that dogs and cats get dewormed regularly to get rid of these pesky parasites, which they can sometimes carry inside them for some time without showing any signs of infection. Your veterinarian will choose a medication based on many factors including your pets age, the time of the year, and how much contact they have with other animals.

Some pretty nasty critters want to live in your pet’s intestines, some of which you can learn about in our previous blog. This blog post will be focusing on another common intestinal worm, the tapeworm.


The two most common types of tapeworms that infect cats and dogs are Dipylidium caninum, and various species of the Taenia tapeworms. Tapeworms are made up of small, flat segments that grow from the head of the worm, which can use a combination of suckers and hooks to attach to the wall of the host’s intestines. Tapeworms absorb nutrients from the intestines through their thin body wall, but it’s generally such a small amount that a healthy host is usually not affected by the parasite. New segments grow and push the older segments further down, forming the tail of the worm. When the older segments have matured, they will be filled with eggs and break off into the intestinal tract to get carried out in the next bowel movement. You may find tapeworm segments stuck to the fur under your pet’s tail, or on whatever surface your pet has slept on. The segments are small and white and resemble a grain of rice, except they may wiggle and move on their own, much unlike a grain of rice.

How does a pet become infected?

The “common tapeworm” (Dipylidium caninum) is spread when a flea larvae eats a tapeworm egg and matures to an adult flea. This gives the tapeworm time to grow to its infective stage inside the flea. Your pet gets infected when it accidentally ingests an infected flea. Accidentally eating a flea may sound unlikely, but fleas can be itchy and sometimes have painful bites, and your pet may respond by biting or licking at the irritating pest. After the infected flea is eaten, the tapeworm can escape into the intestines and attach to the gut wall, where it’ll grow segments to start the cycle again.

The Taenia species is spread when an animal like a rodent, rabbit, or deer eats a tapeworm segment containing eggs. The eggs hatch and the tapeworm larvae migrate through the animal’s body, causing damage as it moves through the organs, before coming to rest in the abdominal wall. When the animal is killed and gets eaten by a dog or cat, the tapeworm enters the intestinal tract of its new host, where it attaches to the wall of the intestine and begins forming segments to shed and start the cycle again.

Why is it bad?

A healthy, adult dog or cat with a low number of tapeworms will not generally show any signs of having a parasitic infection, but finding a wriggling tapeworm segment in your pet’s fur or your home is gross. Pets with a severe infection may show some signs of gastrointestinal upset such as diarrhea or abdominal pain. Very young or very old pets with high energy requirements and lots of tapeworms may show signs of weight loss or undernourishment as they compete with the tapeworm for nutrients. Most cases of tapeworm infections don’t cause significant problems, and are merely treated because of the “ick factor.”

How do you get rid of tapeworms?

The best way to prevent infection by Dipylidium caninum is to prevent and control fleas, and the best way to avoid infections by Taenia worms is to keep your pets from hunting or eating dead animals. Eggs are rarely seen in diagnostic tests, so false negatives are common. The most accurate way to tell if your pet has tapeworms is to see a segment on them or in your house. Luckily it generally only takes one deworming treatment to become tapeworm-free. Some deworming products are effective against other intestinal worms, but not all types of tapeworms, so it’s essential to get the appropriate medication from your veterinarian who will be based on your pet’s circumstances.

Written by Mill Creek Animal Hospital