Worm Infections in Dogs: Diagnosis and Treatment

Worm infections are very common across nearly all breeds of dogs. Deworming is the process of treating (and thereby removing) worms from your pet dog. While it certainly isn’t something that most owners like to think about, knowing how to identify a worm infection (and how to treat one) is important for the health of your dog.

There are five main types of worms that can infect dogs (which are covered in the below sections). Treatment options depend on which type of worm has infected your dog, as well as your dog’s medical history, age, breed, etc. After we describe the main types of worms (and their symptoms), we cover treatment options and prevention tactics.

Five Main Types of Worms in Dogs


This type of worm infection can be fatal in juvenile canines and puppies (if left untreated). In adult dogs, hookworms can cause anemia. This might not sound too bad, however, keep in mind that hookworms from dogs can infect humans (which usually occurs through touching the contaminated stool of the dog).


Roundworm infections affect the intestines of dogs and come in two varieties (T. Canis and T. leonina). There are other types of roundworms (e.g. B. procyonis), however, these aren’t as common as the aforementioned strains.

  • Note: Some strains of roundworms can be passed from dogs to humans. If your dog has any roundworm symptoms it is very important to get them screened at a veterinary clinic as soon as possible.


This type of worm infects a dog’s intestinal tract and colon. Their eggs are passed through the dog’s stool (similar to hookworms). Whipworm eggs can survive for up to five years (in ideal environments). This is why maintaining a clean environment for your dog is essential to its overall health.

While this type of worm doesn’t cause any major symptoms in minor infections, there are many symptoms that present in advanced infections:

  • Inflamed joints/body parts.
  • Loss of weight
  • Diarrhea
  • Anemia


Nearly everyone knows what tapeworms are. This type of worm attaches itself to the intestinal tract of the infected dog and then subsists off of whatever the dog (or host) eats (i.e. whatever passes through the intestines).

Tapeworms appear in the stool of infected animals. If you notice worms in your dog’s stool, you need to get in touch with your veterinarian and bring them the stool (to get tested). Another common symptom of a tapeworm infection is your dog rubbing its backside back and forth on the ground.

Dogs can become infected with tapeworms from fleas, or by eating/coming in contact with other animals who have fleas (or are infected with tapeworms). This is why nearly all veterinarians place such an emphasis on anti-flea medications.


While heartworms can cause very serious complications in dogs (especially older dogs), they can also be prevented quite easily. Because this type of worm is passed through mosquitoes, it’s nearly impossible to completely prevent it. However, anti-heartworm medications are very effective at destroying both heartworms and their offspring/eggs.

Diagnosing Your Dog With Worms

While some types of worm infections can be visibly detected (in your dog’s stool), other types must be detected by lab tests. If you suspect your dog has a worm infection, you’re going to need to get a (fresh) stool sample and deliver it to your veterinarian.

After the vet has received your dog’s stool sample, they will examine it under a microscope (to see if there are worms/eggs). After they’ve determined which type of worm your dog’s been infected with, they will be able to develop a customized treatment plan.

One of the only types of worms that can’t be detected using a stool sample is the heartworm. Vets usually need to take blood work to determine if a dog has heartworms. Sometimes, x-rays or other types of scans are required (because heartworms affect lungs, heart, and other systems within the body).

Treating Worm Infections

Different worm infection types have different treatment options. Depending on which type of worm your dog has been infected with, the vet will prescribe a certain type of deworming medication.

Deworming your dog with Panacur C (a popular deworming medication) is a strategy used by many veterinary clinics. Multi-use dewormers are very popular because they work against numerous types of worm infections.

Many infections are treated over two treatment cycles. The first cycle is used to kill any adult worms, and the second cycle is used to destroy the offspring/eggs of the original worms.