title: [Drug interactions].
abstract: Drug-drug interactions can be used to enhance effectiveness but they are also a significant cause of adverse drug reactions. Alterations in liberation, absorption, distribution, metabolism, and excretion may all affect the pharmacokinetics of a drug. Cytochrome P450 enzymes and drug transporters like ABC-transporters determine the clearance of many drugs leading to alterations in therapeutic effect. In contrast pharmacodynamic drug interactions will alter drug effects in the absence of concentration changes of the co-administered drug. Alterations of a drug effect may require changes in dose to maintain the therapeutic effect.
authors.affiliation: Abteilung Klinische Pharmakologie und Pharmakoepidemiologie, Universität Heidelberg, Heidelberg, Deutschland.
authors.forename: V
authors.initials: V
authors.lastname: Hafner
authors.forename: B
authors.initials: B
authors.lastname: Grün
authors.forename: C
authors.initials: C
authors.lastname: Markert
authors.forename: D
authors.initials: D
authors.lastname: Czock
authors.forename: G
authors.initials: G
authors.lastname: Mikus
authors.forename: W E
authors.initials: WE
authors.lastname: Haefeli
mesh_terms: D004347:Drug Interactions; D064420:Drug-Related Side Effects and Adverse Reactions / Q000139:chemically induced* / Q000191:economics* / Q000517:prevention & control*; D006801:Humans