Leaving anything to chance with prevention can put your pet at risk!

Heartworm prevention is vital to making sure that your pet doesn't contract the deadly disease, and you'd be surprised how many people make one of these heartworm prevention mistakes when trying to protect their furry friend.


Before starting any heartworm prevention medication is it always vital that you take your pet to the vet first. Your vet will be able to perform a simple blood test to detect that your pet is truly heartworm-free. If heartworm prevention is given to an infected pet it can cause the heartworms to die quickly, causing blockages in the heart and lungs which can be fatal.


Some pet owners leave off giving prevention to their pets during the colder seasons because they think mosquitoes are not around and therefore their pet is not at risk. However, you are in fact putting your pet at risk in the case that prevention is stopped too early or started too late. This is definitely a case of “you are better safe than sorry!”


If your pet has put on or lost weight then it is important to check the recommended weight range of your medication. This is not only relevant to heartworm prevention, but flea, tick and other worm prevention as well.

We do not recommend trying to making up for gained weight by breaking up doses and adding them together, or subtracting from a dose for lost weight. It is far safer to just get a new pack that is fit for your pet's weight range.


Heartworm prevention comes in various treatment options. There are spot-ons, oral tablets and chews, meaning that if your pet cannot tolerate one there are other choices out there to try. Some preventions, like Advocate, also treat against fleas and other worms! Make sure what you’re giving your pet is the best for them.


It might surprise you that mosquitos can survive for months indoors, giving a good amount of time for heartworm larvae to mature in the mosquito and infect your pets! Indoor pets are no less at risk of heartworm infection than outdoor pets.


To err is human and missing or giving late doses of prevention is one of the most common mistakes when it comes to protecting our pets. While most products are active for up to 6 weeks, the maximum effectiveness is 4 weeks so given exactly on the month mark is the best way to ensure your pet si protected against deadly heartworms.

If you are prone to missing doses when it comes to prevention for your pet, talk to your vet about getting a yearly or six monthly vaccination. Often, they will send out reminders when your pet is next due so forgetting is a lot less likely.

Check out the range of options for heartworm prevention for dogs and heartworm prevention for cats that are available on Pet Guardians. In this case, prevention is far cheaper and less traumatic on your pet than the cure, so we recommend that you keep your pet up-to-date on their heartworm prevention whatever option you take.

If your pet is showing signs of heartworm infection then it is important to get them to a vet immediately.