The success of drug therapy to some extent does depend on interaction between food and the drug. A food –drug interaction is a condition in which the food affects the activity of a drug. The change most of the time may results in detrimental effect on the patient. Therefore it is advisable for patients to follow the physician and nutritionists instructions to obtain maximum benefits and simultaneously to prevent such unfortunate event. This course will provide information about such interactions and will help nutritionists plan meals cautiously with drugs or suitable food supplement to get maximum benefit for the patient.