The influence of food on drugs is a complex relationship in which the metabolism of the drug plays a crucial role. Drug metabolism is not always a foreseeable process. It may be affected by taking other drugs, interindividual and intraindividual differences, condition of the organism, genetic predisposition and the food we take. Drugs interfere with food in four ways. The first way is ex vivo inactivation of the drug before entering the patient's body. This type of food and drug interaction usually occurs when preparing the application of drug. The second interaction takes place when the drug is already present in the body. This interaction has three subtypes, foods that affect the drug metabolism enzymes, foods that affect the transporters and food that forms insoluble complexes with drug. The third way of interfering food and medication for the consequence has initiating physiological processes in the body that are not foreseen for this drug. The last type of interference implies changes in drug excretion caused by certain nutrients. Although it is known that grape juice should not be consumed with a large number of different drug groups, less attention is paid to other nutrients that have significant drug interactions. This paper lists basic groups of drugs and foods that have a great influence on drug absorption, metabolism and excretion.