Metabolism in the Gastrointestinal Tract: Relevance for Drug Development

For orally administered drugs, metabolism in the gastrointestinal tract (GIT) can decrease the fraction of the dose bioavailable in the systemic circulation (e.g. by first-pass metabolism), but in the case of prodrugs also enable the pharmacologically active moiety to become bioavailable at all. The role of the liver in drug metabolism is widely known and thoroughly investigated. But also the GIT can have a significant role in drug metabolism. The purpose of this paper is to describe these aspects along the consecutive segments of the GIT, i.e. mouth, esophagus, stomach, small intestine, and large intestine.

Publication History

Article published online:
17 November 2021

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