When I took Tabitha, her vet records said she had a barfing problem and that was one of the reasons why they had her on IVD (prescription canned stuff). I gradually weaned her off the stuff and she is now on a teaspoon of canned Iams and a half cup of Science Diet Sensitive Stomach a day (all my cats are). There have been absolutely NO vomiting problems at all. Maybe trying a sensitive stomach formula may help. When she barfed, was it whole food?? If so, she probably ate too much too fast.