What is Lungworm?

Lungworm (Angiostrongylus vasorum) is a parasite infection in dogs. It is now considered endemic in the South East of England.

How can my dog get lungworm?

Dogs become infected by swallowing the worm larvae which are spread by slugs, snails and sometimes frogs. For example, lungworm can be picked up by dogs by simply eating grass or licking the ground that slugs, snails and frogs have previously been on.

What are the clinical signs of lungworm?

Once your dog has ingested the larvae, it will grow inside the body. Once the larvae reaches adulthood they become lungworms. They mainly live in the heart and the blood vessels that lead to the lungs. Due to this the most common clinical signs are;

  • breathing problems
  • coughing
  • exercise intolerance

What you cannot see is that Lungworm can also interfere with blood clotting. This can cause;

  • excessive bleeding from small wounds
  • nose bleeds
  • bleeding into the eyes
  • pale membranes in the eyes and gums (indicating signs of anaemia)
  • bleeding into the brain can cause seizures and behavioural change

Less specific clinical signs include;

  • weight loss
  • poor appetite
  • vomiting
  • diarrhoea

The inability for the blood to clot can cause major problems if an affected dog underwent surgery such as neutering.  They are likely to bleed and we would be unable to stop it resulting in the death of your pet.

Can my dog be tested for lung worm?


Dogs can now be tested for lungworm with an in-house blood test. We can have results within 30 minutes. We can also submit a faecal sample to an outside laboratory for testing. This is best done on a pooled sample over three days to minimise the small risk of a false negative result. Radiographs are likely to have been taken if your dog shows clinical signs and certain changes in the lungs will also help confirm Lungworm.

How is Lungworm treated?

Lungworm is treatable but it depends on how badly your dog is affected. Many dogs will die of Lungworm, even with treatment.

Treatment consists of giving a specific wormer to kill off the lungworms. Advocate will also be given either at the same time or you will be advised to give after the worming course has ended. Other treatments will be given depending on the degree of illness. Some patients will be able to be treated as outpatients, some will need intensive care with us and some will need the help of one of the top vet schools in the country to be able to have a chance of saving them.

How is lungworm prevented?

The prevention of lungworm is simple and you can do it at home.

There are currently two licenced products which are Milpro (trade name may vary) worming tablets and Advocate (trade name may vary) spot on treatment (please see our flea and worm treatment information sheet for the combinations of products that can be used for routine prevention of fleas, ticks, worms and lungworm). This is a prescription-only product so is only available from vets. By using Advocate once monthly and Milpro ever 1-3 months (dependant on veterinary advice) your dog is unlikely to contract lungworm.


If your dog is ill or you think your dog may be infected with lungworm

please call us on 020 8850 3206.


We have seen several cases of lungworm in the practice in the last year and many in the last 15 years since it became a widespread problem.

It really can kill so please talk to us about protecting your dog.

Emmie Beale Bsc (Hons) RVN

Bachelor of science Honours Veterinary Nursing (Bsc Hons)
Registered Veterinary Nurse (RVN)

Call Now ButtonCall Now
%d bloggers like this: