She got those because of her jealousy issues and increasing aggession towards Luna, and since she takes them (we started a few days before she had surgery; here's her thread in Cat Health), she hasn't sprayed so far. The best thing is, she really loves them; I took a video of it today. Hope it works, never tried this so far:
Lily loves her Bach Flower Remedies
(BTW, I know I look awful and sound stupid in that video, hope you don't mind! lol)