What is the most common kind of tapeworm dogs and cats get?

The most common tapeworm of dogs and cats in the United States is called Dipylidium caninum (DIE-pih-LID-ee-um K-nine-um). Infection is common and found throughout the world.

How did my pet get the Dipylidium tapeworm?

By swallowing a flea infected with a tapeworm larvae. A dog or cat may swallow a flea while self-grooming. Once the flea is digested inside the dog or cat, the larval tapeworm is free to develop into an adult tapeworm.

The adult tapeworm is made up of many small segments, called proglottids (pro-GLOT-ids), each about the size of a grain of rice; adult tapeworms may measure 4-28 inches in length. As the tapeworm matures inside the intestines, these segments (proglottids) break off and pass into the stool.

How would I know if my pet has a tapeworm infection?

Although cats and dogs are rarely ill as a result of a Dipylidium tapeworm infection, the proglottids can sometimes be seen crawling near the anus or on the surface of a fresh bowel movement. Proglottids contain tapeworm eggs; these eggs are released into the environment when the proglottid dries out. The dried proglottids are small (about 2 mm), hard and yellowish in color and can sometimes be seen stuck to the hair around the pet's anus.

What kind of problems do tapeworms cause for the dog?

Tapeworms are not usually harmful to your pet. Weight loss may occur if your pet is heavily infected. Sometimes, an infected dog will "scoot" or drag its anus across the ground or carpet because the segments are irritating to the skin in this area.

Occasionally, a portion of this tapeworm will be passed when the dog vomits. If this happens, a worm several inches in length may be seen.