Internal Parasites and Deworming, Shelter and Rescue Resources

Whipworms in Dogs and Cats

Whipworms can affect both dogs and cats. These thin worms live in the large intestine and are usually 45 to 75 mm long. They receive their name from the worm’s shape, which has a thinner front end and wider stout tail, making it resemble a whip.

How Did My Dog Get Whipworms?

The life cycle of a whipworm is simple and direct. Eggs are passed in the feces into the soil, where they are picked up and the process can start all over again. As long as the soil is relatively moist, eggs can live in the soil for years and are resistant to freezing.

Animals become infected with whipworms by ingesting food or drinking water that is contaminated with whipworm eggs. Pets can also become infected by grooming their feet after being in contact with infected soil. After the eggs are swallowed, they hatch and the larvae grow into adults in the large intestine. Then the thin head embeds itself into the intestinal wall and feeds on secretions.

Signs of Whipworm in Dogs and Cats

The symptoms of whipworms in dogs and cats may vary with the severity of the infection and amount of worms in the intestine. Whipworms cause a chronic loose stool consistency often containing mucus and blood flecks. Heavier infestations may cause weight loss, anorexia and diarrhea.

How Do You Know If Your Dog Has Whipworms?

Veterinarians diagnose whipworms by looking under a microscope for eggs in the animal’s feces. They often use a fecal flotation procedure to determine if worm eggs are present.

Cat and Dog Whipworm Treatment

The treatment for whipworms is using a dewormer containing Fenbendazole or Febantel. Mature adults can be removed with an appropriate dewormer, but ingested eggs take two months to mature and are resistant to dewormers. Because immature worms can be resistant to treatment, you will need to give multiple doses for success. Environmental contamination and re-infection with whipworm eggs are difficult to eliminate, but disposing of feces and repeat deworming will be effective at preventing issues.

Whipworm Prevention in Dogs

Preventing re-infection is the key with whipworms. Keeping your animals on a regular worming schedule with a preventative will help control and prevent worms in dogs and cats.

Raised decks for puppies will help prevent infection and break the worm life cycle. You should also pick up feces in the yard or litter box so that the eggs cannot cause re-infection.

If you ever introduce a new pet into your home or facility, you should take precaution and ensure that he is cleared of whipworms to prevent introduction to your other animals. Make sure his vaccinations are up-to-date and deworm with Fenbendazole to prevent whipworm eggs from contaminating your yard.

Want help preventing whipworm and other intestinal parasites? Call our Pet Care Pros at 800.786.4751.

Written by: Marty Greer, DVM

Director of Veterinary Services

Marty Greer, Doctor of Veterinary Medicine, has 40+ years’ experience in veterinary medicine, with special interests in canine reproduction and pediatrics. She received her Doctor of Veterinary Medicine from Iowa State University in 1981. She’s served as Revival’s Director of Veterinary Services since 2019. In 2023, Dr. Greer was named the Westminster Kennel Club Veterinarian of the Year.

If you need help, call us at 800.786.4751.