How Long Should I Give Heartworm Prevention Tablets For?

In this Dr Alex Answers question I discuss how long should you should give heartworm prevention tablets for, and why this will be different depending on the area you live as well as your appetite for risk!


So the person who wrote this in says that their vet tells them that they should give them to her for 9 months and yet a family member's vet says to give it to their dog for 6 months. Who is right? Well, Heartgard was the tablet that was mentioned and absolutely that needs to be given monthly and it's given to prevent serious heartworm infection. Not only is it very serious, but it can also be life-threatening.

Mosquitoes spread heartworm

Now, heartworm is spread by mosquito bites and it's found in all 50 US states and it's also present in Canada. Mosquitoes spread and the risk period is really going to vary depending on which times of the year the mosquito population remains active and that's going to vary massively between different areas. So in some parts of the country, some parts of the world, that might be a year-round risk but in other parts it's going to be a much more narrow window where the potential for your dog to contract and to suffer from heartworm is a risk. So that's really where the big variation is going to be.

Also, while the general recommendation may be given for a specific area, it may be that certain years they need to have a longer treatment period. For example, if an autumn is particularly mild and it might be that mosquitoes are active for longer in the year. If the spring comes early as well, then it might be that where 6 months might normally be able to cover and prevent heartworm infection, you might need to spread it out to 9 months.

And because of this variation and the serious nature of heartworm infection, some people may prefer to play it safe and treat or if their vet recommends treatment with heartworm preventatives like Heartgard tablets for longer than may be absolutely necessary, just airing on the side of caution. So that's definitely something to consider.

Your vet will know the risk to your dog

But you should talk about these things with your vet. They’re going to understand what the local risks are, what the local local risk periods are, what the mosquito activity is and they're going to be the best person to discuss those risks with you and to give the recommendation about what's appropriate for your dog in the part of the world that you're living in.

So what's right for one person may be completely different for others and obviously in other parts of the world or in other parts of the country. Certainly when it comes to Canada, in the far north, heartworm is not going to be a problem.
So definitely talk to your vet and that goes for any parasite control because in different parts of the world we worry about different things. So it might be sandflies when it comes to Leishmania, it might be just fleas and ticks and ticks are particularly prevalent at a certain time of year, but the situation is also always changing.

So while one year you might want to treat for that 6 months, like I say, as time goes on as well and with climate change, that recommendation may change. So definitely check this out with your vet as well.

The above is a transcript taken from “The Dr Alex Answers Show”.

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