After her evening feeding, during which she ingested this new drug, I placed a newly-purchased mat under her litter box. In an attempt to keep the litter as clean as possible, I switched her to Swheat Scoop, a clumping litter made out of wheat. We've had problems with other clumping litters in the past with previous cats, so this looked to be the best of two worlds to me: all natural and able to be quickly cleaned.
Well, she was initially a bit dubious of the mat, but got past that to get into the litter box.
She has yet to leave it for any significant period of time. She's playing with the litter. Pouncing on it, digging into it, batting it about the pan, picking it up in her wee paws, laying in it, rolling in it. All clean litter, mind you, but I can only watch her and think, "My God ... it's full of stars." Her brief forays out of the litter box are full-tilt madcap scrambles after her bug toy. There are occasional side-darts to stave off attacks by the bathrobe belt, the bedsheet or some other pressing danger.
Once the toy has been thoroughly subdued, she carries it back to her litter box to begin the fascination with the litter once again.
I can only hope she comes down by morning when I hope to trim her claws before giving her the next dose.