How to Tell if Your Dog Has Worms
Parasites are not just unpleasant: they can be downright dangerous for dogs. But one big problem with parasites is that it can be hard to tell if your dog is infested. The symptoms of worms in dogs can be similar to those caused by other conditions, which means you need to know what to look for. Read on to learn more about worms in dogs, and how to treat them.
In This Article
Common Worms in Dogs
There are several different types of worms commonly found in dogs:
Roundworms, hookworms, tapeworms, and whipworms are gastrointestinal parasites, which means they live in the intestinal tracts of dogs. Heartworms, on the other hand, infest the hearts and lungs of dogs and can present with different symptoms from intestinal parasites. (In this article, we will mostly be talking about intestinal parasites. However, as heartworms are a serious condition, we’ll also spend a bit of time discussing how to identify them.)
There are many signs of worms in dogs. Some are specific to certain species of worms, while other symptoms, like weight loss, anemia, malaise, and changes in appetite, are more general and can also be symptoms of many other diseases and conditions. Below is a comprehensive list of all the symptoms your dog might experience.
Symptoms of Worms in Dogs
Loss of appetite
Blood in feces (fresh or tarry)
Evidence of worms in feces or around rectum (tapeworms)
Evidence of worms in vomit or feces (roundworms)
Changes in coat condition
Lack of growth (in puppies)
Loss of condition
Coughing, lethargy (heartworms)
Many puppies are born with worms, infected by their mothers transplacentally; others are infected shortly after, while nursing. This is why conscientious breeders follow a deworming schedule under the guidance of their veterinarians, and why puppy owners need to understand the signs. If your puppy is not growing, has a pot-bellied appearance, or is showing any of the other symptoms of worms in dogs, make an appointment with your veterinarian to see if worms—or something else—could be the culprit.
Worms can also affect adult dogs. Heartworms are particularly dangerous for dogs of all ages, and can be fatal if left untreated. Signs of heartworms in dogs include coughing, reduced activity, and malaise.
Intestinal worms can present with a range of symptoms, depending on the type of worm. Some worm larvae migrate through the skin (and other organs), which can cause dermatitis and skin inflammation. In large numbers, most worms can cause anemia as well as weakness, malaise, and changes in appetite and coat condition; weight loss is also common. Severe infestations can lead to other conditions, like pneumonia.
Finally, you may even see physical evidence of worms in your dog’s feces or around their rectum. Worms or worm segments may look like grains of rice or small pieces of spaghetti, but keep in mind they are not always visible.
Dogs can contract worms in a variety of ways, depending on the species of worm.
Transplacental (before puppies are born, via the placenta)
Transmammary (when puppies are nursing, via their mother’s milk)
Transdermal (through the skin)
Contact with infected soil
Contact with infected feces
Eating wild game
Puppies can contract parasites from their mothers, either during pregnancy or while nursing. Roundworms, for instance, can cross the placental barrier, so many puppies are born already infested. Puppies can also ingest hookworms with colostrum, the nutrient-rich milk puppies drink directly after birth.
Hookworms can be transmitted through infected soil. Transdermal infection occurs when this parasite penetrates the skin while dogs lie on infected ground. The eggs are also often ingested by dogs as they play, sniff, and groom themselves in infected areas.
Infected feces can transmit whipworms, hookworms, roundworms, and other parasites, which is why good hygiene around dog poop is crucial for both your health and your dog’s. Other forms of transmission include eating infested game (tapeworms), accidental ingestion of fleas (tapeworms), and mosquito bites (heartworm).
While knowing the symptoms of worms may help you identify a problem, the only way to tell for sure if your dog has worms—and what kind—is to consult your veterinarian. Using microscopic imaging and diagnostic tests, your veterinarian will determine if your dog has worms or another condition. It is always helpful to bring a fresh sample of your dog’s stool to your veterinary appointment.
Once your veterinarian has figured out what type of worm your dog has, you’ll be able to treat it with the appropriate medication. In severe cases, additional steps may also be needed to stabilize your dog until the parasites have been cleared from their system.
Some worms are contagious to humans. Hookworms, tapeworms, and roundworms can all be transmitted to people, and while infestation is not always serious, they can cause problems, especially for small children and people with compromised immune systems.
At this point, you’re probably wondering how to get rid of worms in dogs—after all, thinking about parasites infesting your dog is unsettling! But before you reach for the deworming medications, make sure you consult your veterinarian about the medication that will be most effective for your dog, as well as any necessary supportive care. Bear in mind that puppies may be infested with multiple species of worms, in which case a combination of treatments or a deworming medication that targets all types of worms may be necessary.
The drugs approved for treatment of intestinal parasites in dogs include:
Talk to your veterinarian about the best medication for your dog.
Luckily, worms can be prevented. Some heartworm preventatives and flea and tick preventatives include active ingredients that can help prevent common intestinal parasites. Speak to your veterinarian for advice about the best preventatives for your dog.
Good hygiene is also crucial for maintaining a worm-free environment. Picking up after your dog and preventing them from consuming or sniffing the poop of other dogs—as well as eating wild animal carcasses and droppings—will further reduce the risk of your dog contracting worms.
The idea that your dog could have worms is disconcerting. However, worms are treatable, and the risk of infestations can be reduced with regular preventatives and lifestyle adjustments. If you think your dog might have worms, talk to your veterinarian about the best plan of action—and your pup should be worm-free in no time.