Drug Interactions

The Flockhart Table (TM)

Defining Genetic Influences on Pharmacologic Responses


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This table is designed as a teaching and reference tool for health care providers and researchers interested in drug interactions that are mediated by cytochrome P450 enzymes.

The table contains lists of drugs in columns under the designation of specific cytochrome P450 isoforms. A drug appears in a column if there is published evidence that it is metabolized, at least in part, via that isoform. It does not necessarily follow that the isoform is the principal metabolic pathway in vivo, or that alterations in the rate of the metabolic reaction catalyzed by that isoform will have large effects on the pharmacokinetics of the drug.

The Flockhart Table(TM) only catalogs drug-drug interactions that are mediated by CYPs. Drug-drug interactions caused via other enzymes (e.g., UGTs) are not included in this table. In addition, some of the drugs listed here could be substrates of uptake and efflux drug transporters. However, drug-drug interactions caused by inhibition or induction of drug transporters are not included in this table.


If you use this site in your work, please acknowledge it by citing the following reference:

Flockhart DA, Thacker, D., McDonald, C., Desta, Z. The Flockhart Cytochrome P450 Drug-Drug Interaction Table. Division of Clinical Pharmacology, Indiana University School of Medicine (Updated 2021). https://drug-interactions.medicine.iu.edu/. Accesed [date].

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