CYP2D6 Substrates

    CYP2D6 substrates include, but are not limited to, amitriptyline, amphetamine, atomoxetine, codeine, dextromethorphan, duloxetine, fluoxetine, metoprolol, tamoxifen, and tolterodine. See glossary page for more information.

    Summary

    CYP2D6 substrates are compounds that are metabolized by CYP2D6 (a cytochrome P450 enzyme), but do not necessarily affect its activity.

    In the presence of CYP2D6 inhibitors, the metabolism of CYP2D6 substrates can be reduced. Interestingly, CYP2D6 is not thought to be significantly inducible.

    Compared to other drug-metabolizing CYP enzymes, CYP2D6 demonstrates the highest levels of genetic single-nucleotide polymorphism. This results in varying levels of enzyme function across the population, which can influence the safety and effectiveness of some medications.[1]

    The table below outlines some of the most common or clinically relevant CYP2D6 substrates.[2][3][4] Importantly, this list is not exhaustive.

    CYP2D6 Substrates
    Amitriptyline
    Amphetamine
    Aripiprazole
    Atomoxetine
    Carvedilol
    Chlorpromazine
    Codeine
    Desipramine
    Dextromethorphan*
    Diphenhydramine
    Donepezil
    Duloxetine
    Flecainide
    Fluoxetine
    Galantamine
    Hydrocodone
    Imipramine
    Loratadine
    Metoclopramide
    Metoprolol
    Mirtazapine
    Nortriptyline
    Ondansetron
    Oxycodone
    Paroxetine
    Propranolol
    Tamoxifen*
    Timolol
    Tolterodine
    Tramadol
    Trimipramine
    Venlafaxine

    * Prodrugs are indicated with an asterisk

    References

    1. ^Zhao M, Ma J, Li M, Zhang Y, Jiang B, Zhao X, Huai C, Shen L, Zhang N, He L, Qin SCytochrome P450 Enzymes and Drug Metabolism in Humans.Int J Mol Sci.(2021-Nov-26)
    2. ^Song Y, Li C, Liu G, Liu R, Chen Y, Li W, Cao Z, Zhao B, Lu C, Liu YDrug-Metabolizing Cytochrome P450 Enzymes Have Multifarious Influences on Treatment Outcomes.Clin Pharmacokinet.(2021-May)
    3. ^Zanger UM, Schwab MCytochrome P450 enzymes in drug metabolism: regulation of gene expression, enzyme activities, and impact of genetic variation.Pharmacol Ther.(2013-Apr)
    4. ^Hakkola J, Hukkanen J, Turpeinen M, Pelkonen OInhibition and induction of CYP enzymes in humans: an update.Arch Toxicol.(2020-Nov)