What are the Types of Worms in Dogs?

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Types Of Worms In DogsUnfortunately, worms in dogs are just something that dog owners have to deal with at least a few times during their dog’s life. No matter the kind, they are always unpleasant to deal with and will always need veterinary care to be taken care of. Here, we discuss the different types of worms in dogs, the signs of infection, how to prevent them, and how they’re diagnosed. 

What are Worms in Dogs?

No one wants to think about their pooch going through life with worms crawling around their internal organs, but understanding more about these parasites is important for your dog’s health. When left untreated, any type of worm can lead to serious health problems. Dogs may pick up these parasites from animal feces and then pass them over to other dogs. 

There are also instances when humans can contract certain kinds of worms which is why we must clean up after our dogs. As such, knowing the symptoms, risks, and treatment options available for worms inside dogs is an important part of your responsibility as a dog owner. Moreover, keeping your dog free of parasites is the best way to ensure they won’t have anything negatively impacting their health.  

Symptoms of Worms in Dogs

Different types of intestinal worms will have different effects on the dog’s digestive system but there are a few signs of worms that you can keep in mind. Intestinal parasites may cause the following in dogs: 

  • Lethargy
  • Dehydration
  • Diarrhea
  • Abdominal pain
  • Weight loss
  • Vomiting 
  • Nutritional deficiency
  • Intestinal blockage
  • Pneumonia
  • Nutritional deficiencies
  • Bloody diarrhea
  • Anemia
  • Poor coat appearance
  • Pot-bellied appearance

If your dog has a heartworm infection, your pup may display clinical signs such as weight loss, weak pulse, coughing, abdominal distension, and intolerance for exercise. In severe cases, some dogs may also experience pale gums and labored breathing.  

Common Types of Worms in Dogs

Below are some of the most commonly found types of worms in adult dogs. When left untreated, all of them may lead to serious problems in our dogs’ health. 


These are the most troubling types of worms to have in your dog’s system, but luckily, they’re also the most preventable. Because this parasite is transmitted through mosquito bites, they’re almost impossible to avoid in most areas. Luckily, vets can provide regular heartworm preventatives to help your pup stay safe from heartworm disease. 

When they’re allowed to thrive, they can multiply inside the heart, making way for heart failure, organ damage, and lung disease, ultimately leading to death in the worst-case scenario. Moreover, apart from dogs, coyotes, foxes, and wolves can carry these worms, and because its treatment is expensive, comes with side effects, and is lengthy, prevention is the best thing to do for heartworms. Treatment also involves confinement and exercise restrictions which can be difficult for dogs and their owners. 

Vets recommend regular testing since preventative measures won’t be able to kill heartworms in the adult stage.


A hookworm infection may cause anemia and can even be fatal in puppies if they’re left untreated. While these are very small animals, they’re capable of ingesting large amounts of blood once attached to the dog’s intestines. Dogs may be exposed to hookworm eggs around their environment — dogs can then fall ill as a result of various kinds of hookworms. 

Hookworms, also known as Ancylostoma caninum, can be passed down from the mother dog to her puppies as hookworm larvae travel through the mother’s milk. If infected, your dog’s stool may be home to many microscopic eggs, where they will hatch and live on soil for many months. If your dog feeds on infected dirt, licks on their paws when it comes from an infected area, or sniffs dog feces, it can become an infected dog.   

Veterinarians are capable of diagnosing hookworms through a test called fecal flotation, which is a microscopic version of a stool sample. Because humans can also get these worms, deworming medication is used to treat parasites and is usually given twice. The first time is to catch adult worms and the second time is performed 2 to 4 weeks later to eliminate newly hatched worms.   


This is another worm found in the large intestine of dogs, and there are two types of roundworms: Toxascaris leonina and Toxocara canis (T. canis). The latter is more prevalent in puppies since they can be born with these parasites intact. They may also be transmitted to humans, which is why pups must get the necessary veterinary care.     

Your vet may take a fecal sample to check for roundworm eggs and then treat them with deworming medication. Roundworms can be observed within a dog’s stool or vomit, or roundworm larvae may also be passed to puppies through their mother’s mammary glands. When left untreated, this worm can result in your dog’s poor growth and in extreme cases, even death.

The raccoon roundworm, also known as Baylisascaris procyonis (B. procyonis), is a rare kind of roundworm that may infect dogs around North America. They can enter dogs through infectious eggs and infected dogs such as rabbits, birds, and rodents. Their eggs may be spread from animals to humans, which is why it’s necessary to diagnose them quickly in dogs and to provide the correct treatment promptly. 


Dogs may get this parasite inside their intestinal tract by consuming an infected flea or eating wild animals infected with tapeworm eggs. Once eaten, the eggs will hatch and stick to the intestinal wall, which is why flea control is so important for dogs. The most common type of tapeworm around the United States is the Dipylidium caninum. 

Tapeworm segments can be found in dog poop and are visible to the naked eye and look like grains of rice. Some infected dogs may start scooting as a sign of worm infestations; if you notice your pup doing this, be sure to take a stool sample for your vet to analyze. When the presence of tapeworms can be confirmed, your vet should be able to prescribe a treatment. 

While treatment can be administered orally, fleas will also need to be eliminated from your dog and your home. 


Whipworms can be found in the dog’s intestinal tract and colon, where eggs will travel via the dog’s feces. Dogs can ingest these parasites through animal flesh, feces, soil, food, or water. Whipworm eggs can survive for up to 5 years within a warm and moist environment, and in mild cases, there are no symptoms of infestation. 

However, symptoms of severe cases can include diarrhea, weight loss, inflammation, and anemia occasionally. Adult whipworms can be detected in a dog’s fecal sample, and false negatives aren’t common since they aren’t easy to find. If you notice bloody stool in your dog, it’s best to have repeat fecal exams. 

Most times, your vet will recommend 3 monthly treatments, while keeping your home clean and sanitary as well as cleaning up after your dog is a must for prevention. 

Diagnosing Worms in Dogs

While we might be able to see tapeworms in your dog’s feces, vets will usually be able to diagnose other types of worms in dogs through the microscopic examination of their stool. If your dog displays any of the signs detailed above, then be sure to send your veterinarian a stool sample. This will help them confirm or rule out worms as the reason for their symptoms. 

Even if your pup doesn’t show any kind of symptom, it’s still a good idea to give your vet a stool sample whenever you bring it in for a yearly examination. A blood test will often be used for detecting heartworms, but there are also times when an echocardiogram, radiograph, or ultrasound may be used instead. 

Even if many dogs will show little or won’t show symptoms during the early stages of heartworm disease, giving them treatment as early as possible is the best way to ensure that it will be a success. As such, it’s always a good idea to get your pooch tested once a year for heartworms. 


When looking to contain the spread of intestinal worms in your dogs, regular testing, flea control, and good hygiene are the best practices to keep in mind. Deworming medication, along with preventative medications can help you treat all kinds of intestinal parasites and heartworms. Because puppies are susceptible to getting heartworms from their mother’s milk, it’s best to give them regular stool testing as well. 


There are many different types of worms in dogs, each of which can bring a wide range of health conditions to our dogs if we leave them untreated. Luckily, a simple fecal exam may help identify the kind of infestation your pup has, and how it can be treated. Once taken care of, pet parents must then ensure that they take preventative measures to help keep their dogs protected from these parasites.