[Food intake and resorption of drugs from the gastrointestinal tract]

Abstract

Drugs are mainly absorbed in the small intestine. Therefore, the time course of absorption is not only related to the rate and extent of the release of an active compound from a dosage form, but in addition depends on gastric emptying. Liquid and solid components of gastric contents to a certain degree can be delivered to the duodenum independently of each other. The gastroduodenal transport of solid material in the fasting state differs from the fed pattern of emptying due to the fact that the motor activity of the distal stomach during the digestive period is fundamentally different from fasting motility. Being a major determinant of the gastroduodenal transport of drugs, the motility pattern - fasting or fed pattern - should be included in the definition of "fasting drug application". The entire duration of a digestive period is a function of the type and amount of liquid and solid food ingested with a meal, and of meal frequency. As compared to fasting drug application, the presence of food within the stomach can alter the release of the therapeutic agent from a certain preparation, and can influence the gastroduodenal transport of the active compound, the excipients, or the intact dosage form. Such effects are not specific for a certain substance, but depend on the pharmaceutical formulation. Special attention should be paid to the peculiarities characteristic of enteric coated single unit dosage forms.