Your vet isn't correct here - there are plenty of online reputable vendors, Fosters and Smith being one of them, 1800PetMeds being another one.
As long as you're giving your heartworm every single month, you shouldn't really need to worry too much about the guarantee issue.
__________________ ~ A friend told me I was delusional. I nearly fell off my unicorn. ~
°¨¨¨°ºOº°¨¨¨° Ann | Pfeiffer | Marcel Verdel Purcell | Wylie | Artie °¨¨¨°ºOº°¨¨¨° |