Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Roundworms In Dogs: Our Vet Discusses Signs, Causes & Treatment

beagle dog sick sad on bed

While you may wish that it wasn’t true, dogs do get parasites, both inside their body and on it. Some canines get them quite frequently, even those that spend most of their time indoors. One of the most common types of intestinal parasites is roundworms. When your pup is infested with these invaders, it might not be obvious right away, so here, we explain what roundworms may look like in dogs, how they get in their bodies, and what you can do about it.

divider single dog paw oct 2024

What Are Roundworms?

Roundworms are among the many types of parasitic nematodes that can take up residence in your dog’s intestines. They are named as such because they are round in shape—though “tubular” is a bit more accurate. Many people describe them as looking like cooked spaghetti.

These parasites reside in the intestines because they feed off of partially digested nutrients. One or a few roundworms living in your dog’s guts usually doesn’t cause major health problems, but when many of them are living in there, it becomes a major issue, as they are sucking up the nutrients that your dog needs.

Roundworms can also be transmitted to humans, making this an infestation that you and your dog can share. Properly disposing of your dog’s feces, washing hands after handling their feces and petting them, and keeping your pet updated on regular parasite control and testing are the best ways to keep your own body roundworm-free.

roundworms
Image Credit: Rattiya-Thongdumhyu, Shutterstock

What Are the Signs of Roundworms in Dogs?

Roundworms can affect any dog anywhere, but they are more likely to be noticed in puppies because they can be born with them or get them through nursing and their bodies are so small that they are less able to deal with adversities like roundworms. Also, a small number of roundworms typically won’t cause signs, while a large number likely will.

These signs may include:
  • Vomiting
  • Diarrhea
  • Weight loss
  • Poor hair coat
  • Potbelly
  • Slowed growth
  • Intestinal obstruction

You may also see adult worms in your dog’s vomit or feces. Remember, these things look like pieces of cooked spaghetti, and you may be surprised at just how long they can get.

The signs may come on gradually, so it may take a while to notice changes like weight loss or slowed growth. This is why it’s so important to keep regular appointments with your vet, especially if you have a puppy, to make sure your dog is maintaining a healthy weight and to catch any other slight changes before they become a big deal.

How Do Dogs Get Roundworms?

Roundworms are one of the most common parasites that infect dogs. Microscopic eggs are shed in the dog’s feces, which become infective after several weeks and can survive in the environment for years. Dogs may become infested when they ingest grass, lick soil, or get attached to their paws or fur when walking around. Dogs can also catch them by eating small prey, which can have larvae inside. So, getting roundworms is a fairly easy thing for most dogs. Here’s how it works.

Infested dogs and other animals shed roundworm eggs in their feces. Inside those eggs, the larvae develop over the course of a couple of weeks. That pile of feces or the dirt where the feces were laid then essentially becomes a ticking time bomb, waiting for the next critter to come along.

When another dog enters the area, they can pick up the larvae, usually when they are sniffing or even tasting the interesting things that they find while investigating their environment. Once the larvae enter the dog’s digestive system, they migrate through the walls of the intestines and into various tissues, such as the liver or lungs. The larvae can be coughed up by the lungs, swallowed, and then allowed to mature in the intestines, where they will have a never-ending supply of nutrition from the food that your dog eats. The adults then start to lay eggs, which can be detected on a fecal test done by your veterinarian.

german shepherd dog sniffing the sand
Image Credit: DanaTentis, Pixabay

Another way that dogs get roundworms is as puppies before they are even born. When the parasites are making their journey through a pregnant dog’s body, they can pass through the placenta and into the developing fetuses, causing the puppies to be born with roundworms already in their bodies. Roundworm larvae can also migrate into the mammary glands and enter a puppy’s body when they nurse.

People can get roundworms in the same ways. Typically, they can become exposed when cleaning up their infested dog’s feces and then eating something without washing their hands first. Roundworm infestations tend to be more common in babies and toddlers because they are less discriminate about what they put in their mouths, increasing their chances of picking up a roundworm egg.

divider dog paws 4 oct 2024

How Do I Care for a Dog With Roundworms?

Nobody wants their pup to have a belly full of worms. Not only is it potentially dangerous for them, it’s also a risk for us. This is why routine visits to your veterinarian are so crucial. Most vets will perform fecal tests during a dog’s annual exam to check for roundworm eggs and other internal parasites.

A negative fecal test for a dog that isn’t showing any signs of illness is typically sufficient, especially if they are on any kind of flea, tick, or heartworm preventative. Most of these medications will also affect various internal parasites and keep a dog roundworm-free. However, if your dog is showing signs of a poor hair coat, weight loss, diarrhea, or slowed growth, and the regular fecal flotation test still comes up negative, a fecal antigen test may be in order.

If roundworm eggs are found on a fecal test, your vet will prescribe an appropriate dewormer, typically having you administer one dose right away and another about 2 weeks later. Dewormers can only kill adult worms, not the larvae or eggs. Waiting to give the second dose allows any immature critters to become adults that will be susceptible to the medication. This way, they can be wiped out completely. Also, most heartworm preventatives and even certain flea-and-tick medications will take care of roundworms. The most common and effective dewormers for dogs include fenbendazole, pyrantel pamoate, milbemycin oxime, and moxidectin. It’s important to consult your vet to determine which product is best suited for your dog. However, note that not all of these require a prescription.

Since puppies are especially susceptible to roundworm infestation because they can be born with them or get them through nursing, routine deworming is vital. Your puppy will receive multiple doses of dewormer as they progress through their puppy shot series and beyond. Pregnant dogs should also be dewormed within 3–4 weeks of whelping and then again while nursing to prevent transmission to their puppies.

Most dogs with a roundworm infestation will respond well to the dewormer. Dogs with heavy worm loads may vomit dead worms, or you may see dead worms in your dog’s feces for up to a week or more after treatment. Dogs with very high worm loads may experience an intestinal blockage following treatment due to the massive amounts of dead parasites trying to exit the system. This is rare, but if you see signs of vomiting, not eating, stomach pain, and straining to defecate, see your vet immediately.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's our online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

divider dog paws 2 oct 2024

Frequently Asked Questions (FAQ)

How Long Does It Take to Get Rid of Roundworms in Dogs?

Most dewormers will kill adult roundworms within a day or two of administration. They can’t do anything against larvae or eggs, though, so reinfestation can happen immediately. If your pup has issues with reinfestations of roundworms, your vet may recommend deworming your dog monthly.

Can You Prevent Roundworms in Dogs?

Since roundworm eggs are passed in the feces, keeping your yard clean and your dog away from other animal feces is one of the most important steps in preventing infestations. Deworming your dog regularly is another great way to keep worm issues under control, both roundworms and other parasites. Your vet will establish the most appropriate frequency of administration of the antiparasitic medication for your dog depending on the risk of exposure and environment.

Do I Need to Clean My House If My Dog Has Roundworms?

Since people can get roundworms too, a good, thorough cleaning is typically recommended. Dogs can shed eggs in their feces, so vacuuming and scrubbing floors is a good idea. You should also wash the bedding and furniture that your dog frequents. Wash your hands after handling your dog’s feces or grooming them near the rear end. You’ll also want to deworm all animals in the house at the same time.

divider dog paws 3 oct 2024

Conclusion

Dealing with roundworms can be part of the responsibility of having a dog. They are easily transmitted from dog to dog and even to humans through contact with infested feces or soil. Puppies can also become infested before they are born or while nursing.

To control roundworms, keep your dog on a monthly preventative or get regular fecal testing to check for roundworm eggs. Most of the time, a roundworm infestation won’t severely affect your dog’s health, but it is something that you’ll want to treat immediately, not only to prevent spreading to other dogs or humans but also because heavy worm burdens can lead to nutrient depletion, typically seen as weight loss and a poor coat.


Featured Image Credit: Iryna Imago, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

How Long Do Mini Australian Shepherds Live? Average Lifespan, Data & Care

Several factors affect the lifespan of various dog breeds. Some are controllable, such as diet or veterinary care. Others will play out because...

11 Best Dog Foods for Golden Retrievers in 2025 – Reviews & Top Picks

Golden Retrievers are one of the most beloved dogs in the United States. These friendly and lovable dogs can be prone to specific...

Is Bringing Your Dog to Festivals a Good Idea? Risks & Tips

We love our dogs so much that we want to share every happy experience with them. Many people like to take their dogs...

Can Dogs Eat Tripe? Vet-Reviewed Dietary Guidance

Tripe is the lining of a ruminant’s stomach, which includes cows and sheep. It is safe for human consumption, although it is considered...

More related

How to Calculate Pet Food Dry Matter Basis (With Calculator)

What is dry matter basis and why is it important for pet food? We’ve got the answers—and a calculator—to help you determine the...

10 Best Leather Dog Collars in 2025 – Reviews & Top Picks

  Leather dog collars are stereotypically expensive and high quality. However, in today’s market, this is not always the case. They can also...

How Long Does It Take a Dog to Recover From Being Neutered? Vet-Approved Facts

Neutering is one of the most common surgical procedures performed on dogs (and cats). If you adopt your male dog from a shelter,...

6 Best RV Dog Ramps in 2025: Reviews & Top Picks

Older and undersized dogs love RVing to new locations as much as younger and giant pups, even if they have a more challenging...

Keep reading

Can Dogs Eat Salsa? Vet Approved Facts & FAQs

Salsa is a spicy relish composed of tomatoes, peppers, herbs, limes, onions, and spices. It’s usually paired with tortilla chips as an appetizer, but it can also be used as a topping or filling for tacos, enchiladas, or burritos. Salsa...

Can Dogs Eat Salsa

Annamaet Dog Food Review 2025: Pros, Cons & Final Verdict

Review Summary With healthy, natural ingredients, great research, and different options to meet your dog’s needs, Annamaet definitely stands out. This premium food company has over thirty years of experience in making dry food, and it has consistently given us...

Dogster_Annamaet Dog Food Review

10 Best Dog Foods for Bichon Frises in 2025 – Reviews & Top Picks

There are a few things to consider when looking at reviews for the best dog food for Bichon Frises. Keep in mind that a few of these options include ingredients for specific diets that are not required unless specified by...

Bichon eating

4 Turmeric Recipes for Dogs – Quick, Safe & Healthy (Vet Approved)

Turmeric is a root that is related to ginger, and its scientific name is Curcuma longa. Turmeric has been appreciated in traditional medicine for centuries, as it is known to have many benefits for people and their animals, including dogs....

Turmeric Recipes for Dogs

9 Best Dog Foods for Cavalier King Charles Spaniel in 2025 – Reviews & Top Picks

The Cavalier King Charles Spaniel is a gentle, sweet-natured companion that makes an excellent addition to the family. Unlike some small breeds, the Cavalier King Charles Spaniel does well with children, is easy to train, and does not tend to...

Cavalier King Charles Spaniel puppy hairs stand up

Christmas Dog Treat Recipes: 6 Great Options (Vet Approved)

Christmas is a time for celebration and an excellent excuse to share our appreciation for those we love. If you have a furry four-legged family member, there’s no reason you can’t make them feel special this holiday season, too! Yuletide...

Christmas Dog Treat Recipes

Vets Reveal Top Dog Food Allergens to Watch Out For

Is your dog constantly scratching, dealing with tummy trouble, or battling ear infections? You’re not alone, and food could be part of the puzzle. While food allergies in dogs are less common than many think, knowing the usual suspects can...

Hungry pug dog with food bowl ready to eat

Before You Add Olive Oil to Your Dog’s Bowl – Read This!

You drizzle it on your salad, cook with it, and probably have a bottle sitting proudly on your counter. Olive oil is celebrated for its heart-healthy fats and antioxidants, but what about your dog? Can your furry friend benefit too,...

olive oil