Common Parasites Found on and Inside Dogs

Parasites can cause serious harm to your dog, so it’s important that you understand how to prevent and treat them if one of them gets on or inside your dog. Here are some of the most common parasites that affect dogs:


Tapeworms, or cestodes, are a common parasite found in dogs. They’re flat and segmented worms that live inside your dog’s intestines or lungs. Dogs can catch tapeworms from fleas and other insects like ticks, but they’re also common in dogs living on farms where they may eat an infected rodent or rabbit carcass.

To treat tapeworms, your vet will use a prescription to kill the worms while they’re still inside their host’s body. If you think your dog has this kind of parasite, be sure to talk with them about how best to get rid of it before it becomes too serious!


Heartworms are a parasitic worm that can live in the heart and lungs of your dog. They spread when an infected dog bites another animal, who then becomes infected with heartworms. When a mosquito bites an infected dog, it also becomes infected, transmitting them to other animals through its saliva when it bites them as well.

Symptoms include coughing, difficulty breathing and fainting spells. If left untreated, this disease can be fatal within weeks or months. Heartworm medications kill adult worms by burrowing into their bodies and working their way up to their heads where they release toxins that cause death; they also prevent new larvae from developing into mature adults

It is important to note that prevention is key: if you live in an area where mosquitoes are present year-round (which includes most places), you should use monthly flea medication containing Deet on your pet at all times during the warmer months so he does not get bitten by these insects which could pass along heartworm infection in addition to other diseases like fleas or ticks!


Hookworms are intestinal parasites that can be transmitted through a dog’s feces. Hookworms can cause anemia in dogs, diarrhea and weight loss in dogs. To prevent hookworm infections, you should keep your dog from eating dirt or sand during walks or playing outside. If you see even one worm crawling out of your pet’s anus, it is important to call your veterinarian immediately because this could lead to serious complications if left untreated.


Whipworms are a type of nematode, or roundworm. Whipworms live in the small intestine and can cause diarrhea, weight loss, vomiting and other symptoms. You can get whipworms by having direct contact with an infected dog or by ingesting their eggs in the form of fecal matter. In both cases, it’s important to seek treatment from your vet as soon as possible to avoid further complications like anemia (low red blood cell count) or dehydration from ongoing diarrhea. Some common medications used by vets include ivermectin and levamisole but they may not be effective against all strains of whipworms—make sure you ask your vet which drug(s) will work best for yours!


Roundworms are the most common worm found in dogs. These worms are found in the intestines of your pet, where they lay eggs that are passed out of the body through feces. Roundworms can be transmitted from dog to dog or from an infected flea to a dog, causing anemia and weakness.

Roundworm eggs may also be ingested by other animals such as cats and humans. When people ingest these eggs, it can lead to what’s known as “cysticercosis.” This is when the larval form of roundworms develop into adult worms in tissues around your brain or spinal cord. In this case, medical attention is needed to remove them before they cause serious damage.


Fleas are tiny, wingless insects that feed on the blood of their host. If your dog has fleas, you may notice them jumping off his skin after he’s been playing outside or rolling in grass. Fleas are common in households that have indoor/outdoor pets and can be found in the United States, but they’re most common in warmer climates.

Flea bites cause severe skin irritation and allergic reactions like itching and hair loss. They can also transmit diseases like plague or typhus if your pet gets bitten by an infected flea. To prevent this from happening:

  • Vacuum regularly to remove eggs from carpets and furniture
  • Treat pets with monthly topicals


Ticks are blood-sucking insects that can transmit disease to dogs. They’re more common in warmer climates, rural areas and areas with high grass.

Ticks are found in grass, bushes and trees. If you’re going hiking, camping or hunting with your dog, check them for ticks. If you find one on your dog, remove it with tweezers as soon as possible so that it doesn’t attach itself to their skin permanently!

Tapeworms, heartworms, hookworms, whipworms, roundworms, fleas and ticks are all parasites that can infect your dog.

The most common parasites that can infect your dog are tapeworms, heartworms, hookworms, whipworms, roundworms and fleas.

The most common parasite found on the outside of a dog is fleas. Flea bites will cause your pet to itch and scratch itself and eventually cause hair loss from the constant scratching.


Dogs are living creatures just like us and they need proper care to be healthy. You may think that you have a good grasp on what’s going on with your dog, but they are susceptible to various parasites that can cause them harm. By learning about these common parasites found on and inside dogs, you can prevent them from getting sick. With this knowledge in hand, take the time to schedule regular checkups at your veterinarian or local animal hospital if possible so they can give your pooch the best care possible.