Dog & cat health · Vet-reviewed guide

Worms in Dogs: Types, Signs, and Treatment

Intestinal worms are extremely common in dogs, and the signs are easy to miss until they're advanced. Knowing what to watch for lets you catch them early.

Quick answer: Worms in dogs are common intestinal parasites, and the starting point is that you cannot reliably deworm a dog at home, because the right medicine depends on which worm it is. The main types are roundworms, tapeworms, hookworms, and whipworms, and each needs a specific dewormer, so a generic "get rid of worms" product or a home remedy often misses the actual parasite and is not always the answer.

The reliable path is a fecal test, where a vet examines a stool sample under the microscope to identify the worm, then prescribes the medicine that targets it. Signs include worms or rice-like segments in the stool, a pot-bellied puppy, weight loss, vomiting, diarrhea, or scooting. Several of these worms can also infect people, especially children, which is another reason to treat them properly rather than guess. This guide covers the types, how to recognize them, and how worms are actually diagnosed and treated.

The common types of worm

• Roundworms. The most common; look like spaghetti. Puppies often get them from their mother before or after birth.²
• Tapeworms. Flat, segmented worms whose rice-like segments appear near the anus or in bedding. Dogs get them from swallowing an infected flea. See our tapeworm guide.
• Hookworms. Tiny worms that attach to the gut wall and can cause anemia and dark stool.
• Whipworms. Live in the large intestine and can cause chronic diarrhea; often hard to detect.

A separate parasite, heartworm, is not an intestinal worm and is far more serious; see our dog heartworm guide.

How to recognize worms

You can often guess the worm from what you see: tapeworm segments look like grains of white rice near the rear or in bedding, and roundworms look like spaghetti in stool or vomit. Hookworms and whipworms are usually too small to see and are found on a fecal test.² Other signs include a pot-bellied puppy, weight loss despite eating, dull coat, vomiting, diarrhea, and scooting. Some dogs show no signs, which is why routine fecal checks matter.

Why you can't reliably deworm at home

This is the key point. Because each worm type needs a specific medicine, a random over-the-counter dewormer or a "natural" remedy often does not match the actual parasite, so it fails while the worms continue.² Tapeworms in particular need a specific drug that broad-spectrum products may not cover. A fecal test identifies the culprit so the right medicine is used the first time.

How worms are diagnosed and treated

A vet examines a stool sample under the microscope to find worm eggs, then prescribes a dewormer matched to the parasite.² Most intestinal worms clear well with the correct medication, sometimes repeated. Any prescribed dewormer must be chosen by a vet. See how our vet prescription service works.

A note on people

Some dog worms, including roundworms and hookworms, can infect humans, especially children, through contaminated soil or feces.² Cleaning up promptly, hand-washing, and keeping your dog on vet-guided parasite prevention protect the whole household.

When to see a vet

See a vet if you spot worms, if a puppy is pot-bellied or failing to thrive, or if your dog has ongoing vomiting, diarrhea, or weight loss.² Puppies especially need early, vet-guided deworming.