The idea of tapeworms living inside your dog's gastrointestinal tract is unpleasant, but even more unpleasant is when you can see them in his stool or on his bedding. The most common tapeworm infecting dogs is Dipylidium caninum. Fortunately, the worms are often easy to identify, if you know what to look for, and are usually easy to treat.
How Dogs Get Tapeworms
A dog gets tapeworms from ingesting tapeworm-larvae infected fleas while grooming himself. The baby tapeworm is released during digestion in the dog's stomach. When the worm passes into the intestine, it attaches itself with tiny hooks to the intestinal lining, where it remains and grows. While other tapeworm species can grow up to 25 feet long, Dipylidium caninum usually reaches an adult length of about 6 inches.
Tapeworms are generally not harmful or irritating to the dog except in severe, chronic infestations. Often, the only noticeable symptom is tapeworm segments being passed in the dog's stool. The segments look just like slightly flattened grains of rice and sometimes are passed in small clumps stuck together. They are white or off-white. They are alive and, disconcertingly enough, are often moving in the stool.
These segments are called proglottids and are living, reproductive units containing eggs. This is how tapeworms reproduce--as the proglottids release the eggs, they are eaten by fleas, thus continuing the cycle. They can also be unwittingly eaten by rabbits, birds or even dogs when dropped into grass.
Occasionally, tapeworm segments will travel down the anus and exit. They tickle and irritate the dog, who might sometimes clean himself or "scoot," dragging his rear across the floor. The segments may also be found stuck to the fur around the dog's anus or on his bedding.
Tapeworms are not visibly seen by a veterinarian in a routine fecal test; typically, they are only diagnosed when the segments are noticed. Routine wormers, or topical "spot" treatments for parasites, do not get rid of them.
It is theoretically possible for a human to get tapeworms from a dog, but, to do so, the human would have to either ingest a flea or a tapeworm segment.
The only sure way to keep your dog free of tapeworms is to use veterinarian-prescribed flea treatment. Even then, it is possible for a dog to get tapeworms by ingesting grass on which eggs have been dropped or by eating flea-ridden prey animals such as mice or rabbits.
Treatment is simple and effective. A single dose of Droncit (praziquantel) is given, either by injection or a single pill. This quickly dissolves the tapeworms in the intestine, and they are digested and passed in the stool.