My Greyhound fucking hated his heartworm pill. There was nothing I could find to help him get it down. I asked my vet after about 3 months of fighting him on it, and she goes "have you tried cream cheese?" It's not something I typically buy, but holy shit, how the tables have turned! It's a big pill, the size of a quarter and about 1/2 inch thick. I cut it into 4 pieces roll each piece in cream cheese. It doesn't have to be a big glob or anything, just enough to cover the whole pill. I try to roll it into a ball so he swallows it whole rather than licks it.  If you go this route, I recommend the hard cream cheese instead of the whipped!