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Updated: Jun 16, 2026

Diagonal Method to Measure Synergy Among Any Number of Drugs
Published on: June 21, 2018
[Drug interactions]
1Abteilung Klinische Pharmakologie und Pharmakoepidemiologie, Universität Heidelberg, Heidelberg, Deutschland.
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.
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