What are the symptoms of ascariasis in dogs?

As a dog owner, you know your pup’s normal habits best—so when they act a little off, it’s easy to wonder if something’s wrong. Ascariasis, a common intestinal worm infection, can sneak up on even the most careful pet parents, which is why knowing its signs matters.

Noticing small changes in your dog’s behavior or health can be the first clue something’s off—ascariasis, a common worm infection, often shows signs that are easy to miss if you’re not looking closely. Puppies are especially at risk since they can get the parasite from their mothers, but adult dogs who eat contaminated soil or prey can also catch it.

One of the most obvious symptoms is a potbellied look, even if your dog isn’t overeating—this happens because the worms build up in their intestines and take up space. You might also see them vomiting more than usual, and in some cases, you could spot small, white worms in their vomit or stool. Lethargy is another sign; if your usually energetic pup seems tired and uninterested in play, it’s worth checking in with a vet.

In many regions, regular deworming is recommended by local animal welfare laws, and some areas even require it as part of pet licensing to prevent the spread of parasites to other animals or humans. For example, if you take your dog to a public dog park, keeping them up-to-date on deworming not only follows these rules but also protects other pets who might come into contact with contaminated waste. Skipping these steps could lead to fines or, worse, put your dog and community at risk.

Weight loss is a common symptom too—even if your dog is eating normally, the worms steal nutrients from their body, so they might drop pounds without a clear reason. Diarrhea that’s frequent or has a unusual color can also signal ascariasis, as the infection irritates the intestinal lining. If you have kids at home, it’s extra important to act fast; humans can accidentally ingest worm eggs, leading to their own health issues.

Catching ascariasis early makes treatment simple—most vets will prescribe a dewormer that clears the infection quickly. After treatment, sticking to a regular deworming schedule (usually every 3-6 months, depending on your dog’s age and lifestyle) helps prevent reinfection. Following local laws on pet health not only keeps your dog happy and healthy but also shows you’re a responsible member of the pet community, making outings like trips to the park or walks around the neighborhood safer for everyone.