Heartworm Disease & Our Dogs

We all know how important flea and tick prevention is for your dog, but have you thought about protection from heartworm disease?

What is Heartworm Disease?

Heartworm is a serious and potentially fatal disease caused by parasitic worms that are transmitted to your pet as larvae by mosquitoes. These worms are found in the arteries of the lungs or heart. Dogs are considered the most common host for heartworms.

How can my dog catch Heartworm Disease?

When a mosquito infected with heartworm larvae bites your dog, larvae can enter through the bite wound and a new heartworm infection is established. Over the next few months, these larvae develop in tissues into mature worms that migrate to the heart and blood vessels of the lungs. Adult heartworms can be as long as 30cm and live from five to seven years with some dogs infected by as many as 250 worms at a time.


Why is heartworm prevention important for my dog’s health?

Heartworms interfere with circulation and cause damage to tissues, potentially causing heart failure and death. Treating a heartworm infection is difficult and not without risks. PREVENTION is the best approach.

How can I protect my dog from heartworms?

It is almost impossible to prevent some mosquito bites. Therefore to ensure your dog is protected from heartworm disease you need to kill heartworm larvae from mosquitoes before they develop into harmful adult worms inside the body. This is easily done with medication in the form of tablets or chews, ‘spot on’ treatments or an annual injection.

What product should I use?

  • ProHeart SR-12 injection which protects your dog for 12 months.

This is by far the most superior product to use and our first choice of prevention treatments. 

  • NexGard Spectra monthly chews, also treats most intestinal worms plus fleas & ticks (a top up with another wormer that covers tapeworm is needed every 3-6 months depending on risk) 
  • Simparica Trio monthly tablet, also treats most intestinal worms plus fleas & ticks (a top up with another wormer that covers tapeworm is needed every 3-6 months depending on risk) 
  • Interceptor monthly tablets (also controls most intestinal worms)
  • Sentinel Spectrum monthly tablets (also helps to control fleas & most intestinal worms)

Oral chews need to be given every month to ensure your dog remains heartworm free. Missing just a few doses can leave your dog unprotected and may result in the need for blood tests prior to recommencing prevention treatments.

Recent research showed that 40% of dogs diagnosed as heartworm positive were on owner given monthly heartworm preventatives, highlighting that it’s easy to forget.*

*Heartworm Surveillance Program. Available from: vetsaustralia.com.au/heartworm

Talk to our team about the appropriate heartworm prevention for your dog.

When should I start heartworm prevention for my puppy?

Puppies can be bitten by mosquitoes just like any other dog therefore heartworm prevention is recommended to be started by 12 weeks of age and continued for life to ensure protection from disease. 

What if my dog has not had heartworm prevention before?

If your dog is older than 6 months, talk to your vet about blood tests that should be done PRIOR to commencing preventative medication. This is important to establish if there is an existing heartworm burden as heartworm prevention will not kill adult heartworms and may cause side effects.

What if my dog is not up to date with heartworm prevention?

If your dog has not been given any form of preventative medication, is overdue their annual heartworm injection by more than 3 months, or has missed doses of the oral chews or tablets, we advise having our vet do a blood test to determine of your dog has an existing heartworm infection before recommencing prevention.

What if my dog has Heartworm Disease, is it treatable?

There is some risk involved in treating for heartworms although fatalities are rare. Dogs with poor liver or kidney function are at a higher risk of complications from treatment and severe or long-standing heartworm disease may have caused irreversible damage to the organs.

An injectable drug is given for two days that kills the adult worms over a period of a month. Complete rest is essential after treatment as the dead worms will often lodge in the lungs and be slowly reabsorbed by the body. This is a hazardous period although serious reactions are uncommon. 4 weeks later the dog must then be administered a drug to kill the microfilariae (baby worms) in the blood stream. Finally, 4 weeks after this the dog is tested for the presence of microfilaria to ensure treatment was effective after which heartworm prevention should begin.

Has your dog missed a few monthly heartworm tablets?
Are they overdue their once a year heartworm injection?
Is your dog not getting any form of heartworm prevention?

Then your dog may need a blood test to ensure they are heartworm free.


Call now to book your dogs spot, or head to our online booking system

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