Question :

If my dog’s blood test for heartworm is negative and heartgard has been given monthly for the last 2 yrs. why does he have to have another blood test before my Vet will give me a new prescription. Is Heartgard not 100% effective in protecting him from heartworm?

Answer :

I work in the UK where I have never diagnosed heart worm. I also do not have access to heartguard and have NO experience of that drug. Therefore, I recommend to trust your vet’s opinion rather than mine.

However I looked it up and I feel that, providing that you treat your dog monthly, it would be safe to carry on using it without blood tesing your dog.

Best wishes, Julien

vetstoria.co.uk