What are intestinal parasites, and how do I get rid of them in my dog?

Intestinal parasites are basically mostly worms that live in dogs' intestinal tracts. For instance, there's a roundworm and hookworm that live in the stomach and the small intestines of dogs, and there are tapeworms that live in the large intestines of dogs. There are intestinal parasites that are not worms, such as coccidia and Giardia. They're one-cell organisms that are also considered parasites in the intestinal tract.


Dr. Mary Beth Soverns
Countryside Veterinary Clinic

Are there parasites that live in the bloodstream?

Yes, those are heartworms. They actually are worms. They get injected from a mosquito bite and then they get under the dog's skin, they work their way into the bloodstream, and get all the way to the dog's heart and grow into six-inch to 12-inch-long intestinal worms. They kind of look like spaghetti.

What are external parasites? And what can I do to prevent them?

The most common external parasites we see in dogs, particularly here in Maryland, are fleas. Fleas are large enough that you can see them with the naked eye. They're flat and long, and they crawl through the hair coat.

Ticks are a little larger than a flea, and are much easier to see, especially in a short-coated dog like Georgia here. They like to get places where they can suck blood from the dog, so they like to get on ears and faces, but they could be found anywhere on the dog.

How soon should I bring my dog to the veterinarian if I suspect they may have parasites?

As soon as you see them. If you see a flea, call us. If you see a tick, call us. If your dog's itching a lot like it might have mites on it. That's the thing that's confusing to people at home. The dog is scratching, and is it parasites? Is it an allergy? So as soon as you decide that they have an issue, by all means, bring them in, and we'll sort it out and figure out what's wrong with them.

How will my veterinarian diagnose parasites in my dog?

If it's intestinal parasites, we ask you to bring a stool sample. And if you don't have a stool sample, we can acquire one for you. If we think we're looking for heartworms, we're going to take a blood sample from their leg and look at that under the microscope or send it out for external lab for testing. And if they are topical parasites, we can typically just see them.

Is ringworm a parasite?

Ringworm is actually a fungus. It just has a misnomer that they call it a worm. It is an external skin issue though.

Why is early detection and diagnosis of parasites so important?

Roundworms, hookworms, and whipworms are all in the gastrointestinal system. And they generally get the nutrition from your dog first, and your dog gets the leftover nutrition. So those dogs may be unthrifty, may not be gaining weight, and/or they may have bloody stools. So that would be a very unhealthy situation.

As for the importance of early detection, consider fleas and ticks. Fleas can cause flea allergy dermatitis. Fleas can jump off of one animal onto another animal. They can also jump off of a dog and actually bite people. And so of course, we want to get that taken care of right away.

Ticks are particularly problematic because they can transmit a lot of diseases. The deer tick can transmit Lyme disease. Some of the other ticks can transmit Ehrlichia, anaplasmosis, Babesia, Rocky Mountain spotted fever. They all carry diseases, so it's very important that we find it out right away and take care of it.

The other thing I was going to say, though, is instead of just talking about treating all these intestinal parasites and the external parasites and ear parasites, like ear mites, we really, for the most part, we want to prevent them. So we would like it if you would bring your dog in as a puppy or an adult - when you get them. We make sure that they're negative to start with and then get them on some preventatives so that they won't get intestinal parasites or heartworms or fleas or ticks. That's the ability that we have right now, preventive medicine, so our dogs live healthier lives.

If you still have other questions and you'd like to reach out to us, you can call us directly at (410) 461-2400, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as fast as we can.

Dog Parasites - FAQs


Dr. Mary Beth Soverns
Countryside Veterinary Clinic

If one of my pets has parasites, do all my pets in the home need to receive treatment?

It depends on which parasite you're talking about. Suppose it's fleas, for sure. Any of the animals, including people, can get fleas on them. Ticks can spread from cats to dogs to people. Heartworms are generally transmitted from dog to dog, and it's always through a mosquito. So one dog can't give another dog heartworms unless, of course, it went through a mosquito first. Ringworm can be transmitted from one to the next. Mites (like ear mites) can go from one pet to the next. So it's vital that we figure this out right away, so we don't spread it throughout the family.

Can I get parasites from my dog?

If your dog has fleas, they can carry them in the house, and the fleas might bite you as well. Once a tick comes in on a dog, it can crawl on people as well. There have been perhaps a few instances of people getting heartworms from mosquitoes—from a dog that has it biting a person. Those are the most common things I think you would see.

Is there prevention for dog parasites?

Absolutely. I'm glad you asked. The most important thing we do is, especially when dogs are puppies—at eight, 10, 12 weeks of age—we get them on a preventative to avoid getting roundworms, hookworms, whipworms, tape rooms, giardia, coccidia, fleas, and ticks. We can prevent all of those things by making sure that they're negative to start with and then putting them on medications to prevent them from getting those diseases.

Are parasitic infections serious, or will they go away on their own?

They're never going to go away on their own. Fleas are just going to bite you and your dog. They're going to replicate. They're going to lay eggs. They're going to lay eggs on the dogs and in the environment. They're going to continue to replicate in your home. Ticks may die off and eventually fall off in the environment, but then they're ready to get on another person. Do not rely on the weather or anything else to get rid of them. You're going to need to get some help.

What are the treatments for dog parasites?

If it's intestinal parasites, there's going to be a medication that we give orally that will kill that roundworm, hookworm, whipworm, or tapeworm. Most of those have to be repeated in two to three weeks to break the life cycle so that we don't just get it again from the same source. There is a heartworm preventative. Heartworm preventive is a medication you take once a month to prevent them from getting heartworms when they get bitten by a mosquito. There is a treatment for heartworm disease. It's a serious medication that we have to use. The dogs feel terrible. It's a whole long protocol that takes several months to do. So you just want to prevent it. You don't want to go down the road of having to treat for heartworm disease, but it is available if you need to.

Can I use natural or over-the-counter treatments for my dog?

You can. OTC products are probably safe, but we're not sure they're very effective. The medications that we use here—predominantly Interceptor, Credelio, and Bravecto—are medications that have had an extreme amount of research and safety studies and gone through the process of going through the FDA to ensure they are effective. That's the products that I would use.

What can I do at home to treat or prevent parasite infestations?

If you want to treat intestinal parasites, do things like making sure that you pick up the feces in your dog's yard so that if they did have a parasite that they don't reinfest themselves. Make sure that they don't get into other dogs’ feces, particularly at a dog park. As far as fleas and ticks, you want to use your preventives, but you want to keep your dog nicely groomed, and check on him a lot. Ensure that even when you have your preventatives, you look at them from time to time and make sure that they don't have any parasites on them.

One way to avoid ticks is not going in the areas where tall grass is because that's where the ticks are. You want to be careful that you just avoid those areas whenever ticks are out, which in Maryland is usually during the spring, the summer, the fall, and early winter, so almost all of the months of the year in Maryland.

If you still have other questions and you'd like to reach out to us, you can call us directly at (410) 461-2400, you can email us, or you can reach out on Facebook. But please do reach out, and we'll get back to you as fast as we can.