I've found that ginger is a more effective anti-emetic (for people, including my little patients) than most of the OTC or prescription motion sickness or nausea medications. There's science to back it up, too. It's one area where the herbalists have it all over us "modern" docs. It grows everywhere here in Hawaii, so fresh ginger root is easy to come by; but for everybody else, you can get crystallized ginger at most food stores or health food stores, or try "real" ginger ale. You might check with your vet to see if some form is available for cats.

Aloha,
Mark