Can prevention be used to clear a heartworm infection?

Technically yes, and it's called the slow kill method. It is not recommended anymore. There's a totally different way of treating that now that your veterinarian has to do in a hospital.

Yeah, that's a great question. If you get on the internet, you're going to see many talks about heartworm preventions being a slow kill heartworm treatment. Unfortunately, that is not the case. There has been some recent research with one topical product, as the ingredient moxidectin was shown to at least shorten the adult heartworm lifespan. But it's still not considered an adulticide or something that kills or treats the heartworms. Heartworm prevention is part of the treatment in the sense of preventing further infection, but it's not a treatment for adult heartworms. That is a different treatment that needs to be done that has a much higher likelihood of clearing the infection of the adult worms.

No, prevention should not be used to treat a heartworm infection. Once a dog has been diagnosed with a heartworm infection and its stage is determined, it is recommended that dogs undergo specific treatment with a medication called melarsamine or midicide, as recommended by the American Heartworm Society.

No, none of the heartworm preventions can clear a heartworm infection. The American Heartworm Society does not recommend the slow kill method, which involves keeping a dog on heartworm preventative until the heartworms die naturally. This can take several years, and the preventatives will not treat the adult heartworms. Actual heartworm treatment is required to clear the infection.

It can. It just takes a much longer period of time than the fast kill method that we recommend. So while they're sitting there in that heart during that time, they can actually be causing much more damage.