› Worms in Dogs

Common Worms in Dogs:  Parasites in our FurBabies

Discussing those Common Worms in Dogs and single celled organisms that live in the intestines and hearts of dogs does not make for polite dinner conversation. 

However, if left unchecked, these little creatures can make your dog and even you very ill and could be potentially deadly. 

The most common types of intestinal worms include

  • Roundworms
  • Hookworms
  • Whipworms
  • Tapeworms
  • Dogs can also acquire Coccidia and Giardia, which are single celled organisms.
  • Heartworms

Examples of Worms in Dogs


The most common form of intestinal parasite is the roundworm.  Animals with roundworms pass the infection to others when they shed the worm’s eggs in their stool. 

Other animals will eat the infected feces, walk on it and lick their paw, or drink contaminated water.  Mothers can pass the infections onto their puppies either before birth or during nursing. 

Infected animals can have serious health problems including malnutrition and intestinal issues including diarrhea.  Infected animals pose a risk to people because the eggs can be accidentally eaten or enter through the skin. 

Children are at greatest risk especially if they play in areas with infected feces.  If untreated in people, the larval forms can eventually enter organs and other tissues resulting in damage.


Hookworms are also common in dogs and can be especially dangerous because they bite into the intestinal lining of the dog and suck blood.  If untreated, hookworm infestations can result in potentially life threatening blood loss, weakness, and malnutrition. 

Sadly, humans can also be affected when larvae penetrate the skin.  If hookworm larvae penetrate the skin they can cause "cutaneous larval migrans", a potentially serious and scarring inflammation results.   

The larvae produce severe itching and tunnel-like red areas as they pass through the skin. Symptoms that the dog may show include bloody diarrhea, weight loss, anemia, and progressive weakness.


Whipworms pass their eggs in the feces and other animals become infected by eating infected soil or licking areas of their bodies that have come into contact with the whipworm eggs. 

Whipworms are similar to hookworms in so far as they bury their heads into the lining of the dog’s intestine and such blood, but are not as harmful as the hookworm.  The Whipworm lives in the first section of the dog’s large intestine called the cecum and are often more difficult to detect because they shed few eggs. 

Some of the symptoms that a dog with whipworms may display include chronic weight loss, and feces that seems to have a  lightring of mucus.  Whipworms rarely infect humans.


Tapeworms are the only worm you can actually detect without the aid of a microscope.  They are thin flat-segmented worms that are passed from animal to animal when the dog eats infected fleas or lice. 

They can also get certain types of tapeworms by eating infected rodents.  The dog will pass segments of the worm that can be detected under the tail or in the stool.  They look like flattened grains of white rice.  People do not generally get dog tapeworms.


Coccidia are single celled parasites that can only be seen under a microscope.  The dog becomes infected by eating infected soil or licking contaminated paws or fur. 

Once inside the pet, coccidia damage the lining of the intestine keeping your dog from absorbing nutrients. 

Symptoms include watery, bloody diarrhea.  Dehydration is also likely.  Medicines can be given to prevent the parasite from multiplying and allow time for your pet’s immune system to kill the parasite.

Read More about Coccidia.


Giardia in dogs is another annoying parasite that can affect your dog’s health.  This small protozoan, Giardia is not a worm, but a one-celled organism that is also capable of causing harm in many animals including people, although it’s not entirely clear how common the transmission is between dogs and people. 

Once apart of your environment, its hard to get rid of, but there are treatment options available. 

Read more about giardia in dogs.


All of the parasites on this page so far, live in the intestinal tract of your dog.  Heartworms, as the name implies, is different.  Heartworms live in the dog's heart and surrounding large blood vessels.  This is a life threatening condition and expensive and difficult to treat.  The good news is that it is entirely preventable by giving the dog a once-monthly medication by mouth.

Read more about Heartworms

Risk Factors for Common Worms in Dogs

Four scenarios put dogs at risk for worms: 

  • Newborn Puppies:    Roundworm eggs can form cysts in adult dogs and that remain dormant.  When a female dog is pregnant, these dormant eggs will activate and infect the puppies.  The mother's milk can also pass roundworms to puppies.
  • Contact with infected dirt - Roundworm eggs and hookworm larvae can reside in dirt.  If you dog runs into infected dirt while on a walk, at a dog park, or out in the wild, your dog may get worms.
  • Fleas - Young tapeworms can reside in fleas.  If your dog swallows fleas while licking a paw or other part of his body, he could ingest tapeworms and be infected.
  • Hunting or eating wildlife - wild animals may carry worms, including tapeworms residing in fleas on wild animals.  If your dog hunts or eats wildlife, your dog may swallow worms

Diagnosis of Common worms in Dogs

A veterinarian can perform a simple fecal test and prescribe a de-wormer.  Nowadays most monthly heartworm preventatives also prevent some intestinal worms. 

Treatment for Common Worms in Dogs

There are a few medications on the market today that will take care of the parasites in inhabit your dog.

To treat the coccidia organisms, veterinarians will use drugs  such as sulfadimethoxine (Albon®) and trimethoprim-sulfadiazine (Tribrissen®)

Heartgard Plus**Tri-Heart Plus**Iverhart Plus** treats roundworms and hookworms as well as preventing Heartworm.  Their main ingredients are ivermectin and pyrantel pamoate.

Drugs such as Nemex-2** contain pyrantel pamoate and treat roundworms and hookworms.  Drugs such as Panacur** and Safegard** are used to treat roundworms, hookworms, whipworms and tapeworms. 

Prevention of Common Worms in Dogs

  • Keeping fleas away from the dog will also prevent tapeworm infections. 
  • Do not let your dog roam and hunt; raw meat, carrion, or parts of dead animals that are likely carriers of parasites.
  • Keep your grass mowed and pick up feces frequently.
  • Keep up to date with monthly heartworm medication

To protect yourself and your family the best preventative is good hygiene, which means:

  • Wash hands frequently
  • Keep sandboxes covered
  • Wear shoes when outdoors.

Photographs on this page are courtesy of Creative Commons

Grab Our Free Ezine...

Enter Your E-mail Address
Enter Your First Name (optional)

Don't worry — your e-mail address is totally secure.
I promise to use it only to send you Small Dog E-Zine.

Did you find this article  helpful?  Then why not share it.

The best way to say, Thank You?

Is to Share

Contact | Home

New! Comments

Have your say about what you just read! Leave me a comment in the box below.