All About Whipworms in Dogs

Pesky parasites are a common annoyance for our canine companions, and whipworms in dogs doesn’t sound like something you (or your dog!) ever want to encounter. Learn everything you need to know about whipworms in dogs, from diagnosis to treatment and prevention.

One of the most diagnosed intestinal parasites in dogs, Trichuris vulpis’ common name comes from its characteristic whip-shaped body. Whipworms also are related to several other common worms.

“They are parasitic nematodes and, therefore, cousins to hookworms and roundworms, [as well as] nonparasitic worms, such as earthworms,” says Rick Marrinson, DVM, of Longwood Veterinary Clinic in Longwood, Florida.

Whipworms lay microscopic eggs shaped like an oval casserole dish with “handles” at each end. These eggs typically are found in dogs, foxes and coyotes, and, once hatched, live in the colon or large intestine of their host, says Dr. Marrinson, a member of the board of directors for the Companion Animal Parasite Council (CAPC).

Whipworms mostly are found in dogs in the South and Southeast regions of the United States, though dogs who live in any part of the country are susceptible, according to the CAPC’s online prevalence map.

Adult female whipworms release eggs that pass from the host in the host’s feces, Dr. Marrinson says.

“Once in the environment, the eggs are very resistant to drying, temperature extremes and ultraviolet radiation,” Dr. Marrinson says. “They can remain viable in the environment for years. Animals are exposed when they ingest the eggs from the ground and soil or from eating the stool of an infected animal.”

This means that whipworm eggs are quite hearty and can live in dog poop or the soil for many years, waiting to find a host. It’s worth noting that whipworms in dogs are unlikely to be transmitted to humans.

“Many mammals, including humans, have their own species of whipworm,” Dr. Marrinson says. “The whipworm found in dogs is thought to rarely, if ever, infect humans.”

It’s common for dogs infected with whipworms to appear completely normal to a pet parent. In some cases, a dog might experience an upset lower G.I. tract and might even have a few accidents in the house.

“Because whipworms live in the large intestine, they cause symptoms of colitis or inflammation of the colon,” Dr. Marrinson says.

Signs include:

• Diarrhea that often contains either bright-red blood or mucus
• Straining to defecate
• Frequent attempts to defecate
• Urgency to defecate.

“This urgency [to defecate] often causes dogs to have inappropriate bowel movements in the house,” Dr. Marrinson says.

In severe infections, a dog suffering from dehydration, weight loss and anemia can be signs of worms in dogs.

Most whipworm infections in dogs go undetected by pet parents, and only a veterinarian can provide a diagnosis of whipworms.

“While pet parents would readily recognize the symptoms associated with colitis, it would be impossible for an owner to know if those symptoms are caused by whipworms,” Dr. Marrinson says.

It might sound icky, but collecting a sample of your dog’s poop and having it tested at a veterinary clinic will result in a definitive diagnosis. This test is called an intestinal parasite screen or a fecal floatation. The dog’s stool sample is treated with a special solution and then examined under a microscope by a veterinarian to search for those distinctly shaped whipworm eggs.

“Whipworms can be difficult to diagnose because the females are not prolific egg producers,” Dr. Marrinson says. “Therefore, it is hard to reliably find the eggs, even if the dog is infected.”

Although often tricky to diagnose, whipworms are easy to clear up.

“There are a variety of safe and effective treatments for whipworms,” Dr. Marrinson says. “Veterinarians sometimes choose to treat a patient with colitis for whipworms on the mere suspicion of a whipworm infection, even if the intestinal parasite screen showed no parasites. This is especially true if the patient is not on parasite preventive medication.”

You can get over-the-counter or prescription parasite pet meds. But always consult your veterinarian before administering any kind of treatment for intestinal parasites.

“Your veterinarian is the best local source for information on available products and risks in your area,” Dr. Marrinson says.

An ounce of prevention is worth a pound of cure! Preventing whipworms in dogs is no exception, and regular monthly use of broad-spectrum parasite preventives should do the trick.

“Administering parasite preventive medication every 30 days all year long is a critical factor in keeping your pet healthy,” Dr. Marrinson says. “Some, but not all, parasite preventive medications are effective at preventing whipworms,” so it’s crucial to consult your veterinarian.

Many prescription heartworm medicine for dogs also inhibit other internal parasites, such as whipworms, hookworms and roundworms. And some varieties prevent external parasites, such as fleas, as well.

It’s also important to consider your dog’s social habits, including visiting dog parks or other canine playmates, when taking care to prevent parasites. Whipworms are quite contagious among dogs, so Dr. Marrinson encourages excellent hygiene practices.

“Good sanitation, such as picking up and safely disposing of feces, are important steps” he says.