Someone makes citrus scented kitty litter for cats who (as is well known) detest and avoid citrus scents? (I do too becaus ehtye do horrible things to my sinuses.) There's a marketing decision for you.

Have you tried ice cream for the medication? A vet I know (well, Thoraiya Dyer) suggested it for Felix's meds, but he is supremely uninterested in anything dairy. Thoraiya says it's the best, and it would have worked for our old Brucey, who always used to lick the ice cream bowl.