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Key points you need to know about intestinal worms in dogs

Every pet owner has either come up against, or heard of, the notorious ‘worms’ before, but if you’re not quite sure what they are, we’re here to help. We’ll take you through what they are, how to diagnose intestinal worms, and how to treat them.


What are dog worms?

Dogs are often victim to intestinal parasites, otherwise known as worms. Generally speaking the most common intestinal variety are roundworms, hookworms, whipworms and tapeworms. With the naked eye you can only see two – roundworms and tapeworms – while the other two will need a vet to study more closely. It is also worthwhile to note that dogs are also susceptible to heartworms and lungworms, which are becoming more prevalent in the UK, however this guide focusses purely on intestinal worms. Let’s take a look at the four most common intestinal worms in detail:  



In total there are two species of roundworm that can affect dogs – toxascaris leonine and toxocara canis. They appear like spaghetti and survive by absorbing nutrients from your dog. Generally speaking they will remain in your dog’s intestinal tract, but there is the risk that they can spread to organs or surrounding body tissue. Toxacara canis will work their way up through the lungs, where they’ll be coughed up, swallowed and head their way back to the intestines. Toxascaris leonine generally remain in one place and as such survive longer than their mobile counterpart.  



Tapeworms make their home in the small intestine, latching themselves to the wall with tiny rows of teeth – this is how they absorb nutrients to survive. They are long and can stretch to half a foot in length (and sometimes longer), but are generally harmless unless the dog is extremely active. Parts of the worm will break off through the digestive process and appear as small grains on rice in stools – hence they’re easy to spot.  



Whipworms set up camp in the large intestine and generally get by with less nutrients than other worms. The only danger comes if they burrow their way into intestinal tissue, otherwise they’re not known for causing issues. Whipworms aren’t common in the UK.  



Out of all the worms mentioned Hookworms pose the greatest threat, especially to young puppies. They are short and suck blood from their host, but fortunately they’re not common in the UK. Hookworms make their way through the lungs and re-enter the system once coughed up and swallowed again.  


What are the common symptoms of worms?

While worms won’t trigger many, if any, outward symptoms, roundworms do have the potential to cause your dog discomfort. If your dog is experiencing any of the below we recommend taking them to a vet:

  • Swollen abdomen
  • Vomiting
  • Lethargy
  • Diarrhoea
  • Dehydration
  • Coughing
  • Blocked intestine
  • Difficulty breathing


How do worms spread?

Puppies and adult dogs can catch worms in a variety of ways:

  • From their mother (hookworms and roundworms)
  • Eating contaminated soil or faeces (roundworms, hookworms and whipworms)
  • Eating infected animals (all four)
  • From infected fleas (tapeworms only)
  • Walking on contaminated soil (hookworms only)


Dog to human worm contraction

It’s possible to contract worms from dogs, so it’s important to follow a good worming plan. Generally speaking it’s roundworm that is passed on, with children affected more than adults. These worms generally cause no symptoms in humans, but toxocariasis can occur, with a light cough, headache and stomach cramps being the main issues. In rare cases more serious symptoms will occur. Prevention is Key!   


How often should I worm my dog?

It is recommended that you have your adult dog wormed once every three months. It is worthwhile to note that unneutered or pregnant/lactating female dogs have additional worming needs. If your dog experiences flea problems on a regular basis we recommend you get your dog wormed more often. Treating your dog for fleas is really important for your dog’s health as these problems often go hand in hand and it’s difficult to prevent one if the other is present. To have a good preventive medicine regarding worms, it’s always good to combine worming tablets (usually more focused on intestinal worms) and spot on treatment (flea treatment + heartworm and lungworm treatment). Consult your Vet for advice on the correct products for your pet. Puppies on the other hand should be wormed more often – every 2 to 3 weeks up until the age of 12 weeks. Then they can jump on the regular adult cycle of once every three months. Puppy worming is vital for your dog’s healthy growth and, should be one of the top items on your list. Before starting any treatment plan, it is important to consult your Vet for more advice on the correct treatment plan for your pet.