Is it possible to become immune to the effects of cumadin/warfarin? i have been taking it since heart surgery and the dose has steadily increased.

Diet related: We often see patient's diets changing after they recover from surgery. Increased amounts of vitamin k intake create a need for higher Coumadin (warfarin) dosing.

Probably not: Many, many things can affect how well Coumadin (warfarin) works for you. Diet plays a big role, as dr. Everett said. Other medicines can have an affect. Genetics can play a role--certain southeast Asian populations need higher doses than average. Also forgetting a dose every now and then comes into play as well.