Identifying and Treating Parasites in Dogs

Dogs are parasites’s favorite meal. A parasite is an organism that lives in or on another organism and takes its nutrients from it, usually to the detriment of its host. This can be deadly for dogs because parasites sap their energy and rob them of vital nutrients. The good news is that there are effective ways to detect and treat the most common parasites in dogs. So keep reading to learn about some of these parasites and what you can do about them!


Tapeworms are flat, segmented worms that inhabit the small intestine of dogs. They are transmitted to dogs via fleas and can also be passed on to humans through the ingestion of tapeworm eggs found in flea dirt.

The signs of tapeworm infestation include:

  • Weight loss
  • Bloody stools (occasionally)
  • Vomiting (rare)

Tapeworm medication is available from your vet, who will conduct a fecal analysis to determine if your dog is infected with this parasite.


Hookworm is a parasite that lives in the intestines of dogs, cats and other mammals. Hookworms are generally transmitted by contaminated soil (such as a dog’s paws or human shoes) or through contact with another animal, such as a mother hookworm transmitting hookworms to her puppies.

Hookworms can cause anemia and weight loss, which are both serious issues if left untreated. When they enter the body through skin wounds, nosebleeds and open sores are common ways for them to enter your dog’s system—although it’s possible for you to contract this infection yourself if you come into contact with contaminated soil or infected animals.


Whipworm is a parasite that can be passed from dog to dog. It also can be passed from dog to human in rare cases. Whipworms live in the dog’s small intestine, where they feed on food that passes through it. These parasites are more common in puppies and young dogs than adults, but older dogs may also get whipworms if their immune system is compromised by other health issues or medicines.

Roundworm (Toxocara)

Roundworms, also called Toxocara or Toxascaris, are the most common worm in puppies. They’re also the most common worm in adult dogs, cats and humans. Roundworm eggs are passed through stool and then ingested by another animal or human — usually via fleas. In dogs and cats that have not been dewormed for several months (or years), roundworms can migrate through into the eyes, causing blindness if left untreated.

Roundworms can pass from dog to human through contact with infected feces or soil where it has been deposited by a pet undergoing an infection of roundworm larvae. Consuming food contaminated with roundworm eggs can also cause infection in humans but is less common than direct contact with infected pets’ feces or soil containing them (which is why you should always wash your hands after handling any pet).


Heartworm is a serious disease that can be fatal to dogs. Heartworm is spread by mosquitoes; it gets into the dog’s bloodstream, where it travels to the heart and lungs. If you have a pet at home, make sure they are protected from mosquitoes with bug spray or repellent.

If your dog develops heartworm, it can be treated but it is expensive and difficult for the dog to endure. It’s best to avoid this disease by taking preventative measures: buying your pet a monthly pill that will kill any heartworms before they become problematic and being vigilant about keeping them from mosquito bites.

Know your dog’s body and its stool.

To begin, it is important to know your dog’s body and its stool. By becoming familiar with the normal appearance of your dog’s stool (the feces), you can then know what abnormal looks like. It is especially important for owners to be able to discern when their dog has a parasite infection because many parasites are transmitted through food or water that contaminates their dogs’ systems.

  • Tapeworms are segmented worms that can grow up to 30 feet long! They infest the small intestine and cause malnourishment due to blockage of nutrients from getting absorbed into the bloodstream. They look like rice grains in the feces, but are actually segments of tapeworms being expelled by the host organism as they grow larger over time.
  • Hookworms are blood-sucking worms which attach themselves onto intestinal walls causing anemia (a lack of red blood cells). Hookworms also cause bloody stools due to internal bleeding caused by these parasites attaching themselves onto intestinal walls.
  • Whipworms live in large numbers within an infected person’s intestines where they feed on nutrients from foods consumed by their host organism.
  • Roundworms live inside an infected person’s intestines where they feed on nutrients from foods consumed by their host organism.


While the thought of having worms or parasites in your dog can be quite alarming, remember that they are completely treatable. It’s important to take good care of your pet’s health by following all the required vaccinations and regularly visiting the vet. Don’t forget to follow up on any heartworm prevention medicine with an annual test, too!