Understanding Roundworms in Dogs

Posted on: 22 May 2015

Roundworms are intestinal parasites that live on the contents of your dog's gut. These parasites look like strands of spaghetti, can grow to 20cm and can migrate from your dog's intestines to their lungs and liver, leaving them feeling generally unwell.

Adult dogs respond well to roundworm treatment, but roundworms are particularly harmful to puppies whose immune systems are still developing. Roundworms can actually be fatal in puppies, especially if there is a large accumulation of the worms in their intestines, which can lead to bowel obstruction and rupturing. Here's what you need to know about roundworms in dogs.

Causes & Symptoms

Puppies can be born with roundworms if their mother was infected during pregnancy. Adult dogs can be exposed to the parasites through infected faeces, vomit and sharing food with an infected dog. Symptoms of a roundworm infestation include

  • Distended abdomen
  • Vomiting
  • Loss of appetite
  • Dehydration
  • Lethargy
  • Weight loss
  • Worms in the dog's faeces
  • Coughing if worms are in the dog's lungs

Diagnosis & Treatment

Your vet will examine your dog's abdomen and take a stool sample, which will be analysed for the presence of roundworm larvae. Once roundworms have been confirmed your vet will prescribe medication to kill the worms and their larvae. Your dog will also be treated for any complications resulting from the roundworm infestation such as dehydration, which is remedied with intravenous fluids. Once your dog has been treated, keep a close eye on them in order to spot any signs the infestation is still present.


The suffering caused to your dog by roundworms can be prevented by administering worming treatment at home on a regular basis. Puppies should be wormed every two weeks with a product suitable for their age and size. Adult dogs should be wormed at least every three months, but can be wormed monthly. Your vet can advise you on the best worming products for your pet.

Additionally, try not to let your dog share food or water bowls with other dogs or smell or eat faeces when you take them for a walk. If your dog contracts roundworms, you'll have to treat any other dogs you have whether they are showing symptoms or not as roundworms are highly contagious.

If your dog is showing signs of a roundworm infestation or if they haven't been wormed for a while, schedule an appointment with your vet through clinics like Melton Veterinary Clinic.