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Signs Of Worms In Dogs Poop: What It Means, And What You Should Do

Written by Ella White


elegant poodle chilling on armchair

Picking up your dog’s poop isn’t pleasant at the best of times. But when you find worms in there, it’s even more of a shock. But don’t worry – surprising as it is, it’s a fairly common issue in dogs.

Worms are highly contagious and can easily go undetected. But if left untreated, they can lead to serious health conditions. Here’s what signs of worms in dog poop means, and what you should do about it.

There are five main types of worms that commonly affect dogs, and some kinds of dogs are more prone to some kinds of worms than others.

1. Roundworms

One of the most common intestinal worms, roundworms can often become infected by ingesting infected hosts including rabbits, birds, rodents, and even eggs. It’s also common in puppies that obtain it from their infected mother. It can lead to affected growth and, in severe cases, death. 

This is why it’s especially important for puppies to receive full veterinary care when they are newborns. Luckily, roundworms are easily diagnosed through stool samples and treated with deworming medications.

2. Tapeworms

Tapeworms are obtained by eating other animals that are infected, or ingesting infected fleas. They are an intestinal parasite that hatches in the intestinal lining – and they’re a good reason to ensure your dog is fully treated against fleas.

When passed out in dog poop, tapeworms look like small pieces of rice. This is because the whole worm is rarely passed in one go. If you notice your dog rubbing their bottom along the floor to get at an awkwardly-placed itch, passing a tapeworm could be the reason. An oral or injected treatment can be administered, alongside suggested flea treatments.

3. Hookworms

Another intestinal parasite, hookworms are obtained by ingesting hookworm larvae, or in puppies by drinking infected milk from their mother. Though tiny, hookworms can ingest large amounts of blood and lead to anemia in dogs if left untreated

Hookworms are passed in the stool and can remain alive for months. This means dogs risk licking the infected dirt or their paws and becoming infected – and they can also pass the infection on to humans. A vet can diagnose hookworms with a stool sample and will prescribe deworming medications, usually twice: once to catch the living worms, and once again later to catch the eggs that have since developed.

4. Whipworms

Because mild cases of whipworm don’t cause any symptoms, they can go untreated for a long time. Whipworm can be ingested from infected soil, food, water, and even animal flesh and feces. They live in the large intestine and colon, and pass their eggs on through the dog’s poop.

So if you’re not hot on cleaning up after your dog, here’s one more reason why you should be. Whipworms can live up to five years in warm, moist environments after they’ve been passed through a dog. They’re not easy to spot in dog poop so if left to thrive, they hold high risk of reinfection. 

Symptoms of whipworm include diarrhea, inflammation, weight loss, and sometimes anemia. It can be treated in three rounds of deworming medication prescribed by vets.

5. Heartworms

Heartworms are easily preventable, but are also the most devastating if your dog does become infected. Transmitted by mosquitoes, they multiply in the heart and can cause heart failure, lung disease, organ damage and, if left untreated, death.

For this reason, all dogs should be administered with heartworm prevention medicines – but especially those that live in areas prone to mosquitoes. If your dog does get infected with heartworm they will likely need to quarantine and have their exercise restricted. Medical treatments are available, but they are expensive and can take a long time to complete.

There are various symptoms that are displayed depending on the kind of worms your dog has. However tapeworms, hookworms, and ringworms that all live in the intestine often cause the following symptoms:

  • Diarrhea
  • Vomiting
  • Lethargy
  • Dehydration
  • Abdominal pain
  • Bloated belly
  • Weight loss
  • Poor quality coat
  • Exhaustion
  • Anemia and nutritional deficiencies
  • Bright red or dark purple blood in feces
  • Intestinal blockages
  • Pneumonia

As they live in the chest, heartworms can cause symptoms including:

  • Coughing
  • Weight loss
  • Lack of activity
  • Weak pulse
  • Difficulty breathing 
  • Pale gums

Each worm also looks different when it is passed through your dog’s poop:

  • Hookworms are very small and thin with hook-like mouths
  • Whipworms are enlarged on one end and look like tiny pieces of thread
  • Roundworms are thicker and can look like spaghetti. They vary in size and can be inches long
  • Tapeworm eggs look like grains of rice
  • Heartworms are not usually found in dog poop

If you notice any of these symptoms or spot worms or eggs in your dog’s poop, seek medical advice immediately.

Though you might notice larger worms, like tapeworms, in your dog’s poop, it can be hard to spot smaller species. Eggs, especially, can be microscopic and very difficult for the human eye to detect. 

So if your dog is displaying any of the common symptoms of worm infection, your vet will probably ask for a stool sample to be examined. In cases of heartworm, a blood sample may be required. 

Many vets will also check for worms during your dog’s regular health checks.

The good news is that if you do spot worms in your dog’s poop – or if they’re displaying symptoms of worm infection – it can usually be easily treated with deworming medication. Dewormers kill adult worms, and can be administered orally in chew form or as liquid medication, by injection, and sometimes topically.

In some cases, dogs will be prescribed more than one round of deworming treatment to catch any new worms that had not yet hatched during the first dose of medication. After treatment, you will notice worms in your dog’s poop and vomit, but don’t worry – that means it’s working.

Many dogs take a monthly worm prevention medication to prevent parasites from surviving in their intestines. It kills existing parasites and, once worm-free, significantly decreases their chances of reinfection.

It’s also recommended that dogs have their poop checked every 6-12 months to make sure there’s no microscopic parasite eggs that the medication has missed.

There are many elements that contribute to the severity of your dog’s illness as a result of worms. Most dogs can remain healthy with mild symptoms – especially if treated early. However, the following factors will make a difference:

  • Your dog’s age
  • Your dog’s size
  • The type of worms they have
  • How many worms they are infected with
  • Your dog’s overall health

Smaller, younger, and less healthy dogs are at greater risk of more severe health issues after a bout of worms. So even if you believe your dog has never had worms before, it’s important to always take preventative measures. Especially when they’re puppies.