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Ultrarapid clozapine metabolism and CYP2D6 gene duplication in a patient with schizophrenia

    Dorgival Caetano

    Blacktown Mental Health Service, WSLHD, Blacktown, Australia

    Blacktown Clinical School and Research Centre, WSLHD, Blacktown, 2148, Australia

    &
    Irina Piatkov

    *Author for correspondence:

    E-mail Address: irina.piatkov@health.nsw.gov.au

    Blacktown Clinical School and Research Centre, WSLHD, Blacktown, 2148, Australia

    Published Online:https://doi.org/10.2217/pme.15.56

    An optimal clozapine serum level is required for both optimization of clinical response and minimization of troublesome or some of the life-threatening side effects. Serum levels can be influenced by comedication that can cause phenoconversion. When norclozapine/clozapine serum levels and ratios are consistently and significantly lower/higher than expected and there are no concomitant drugs that could account for these findings, further investigation of the genetic variants of CYP1A2, 2D6 and 3A4 are warranted.

    Papers of special note have been highlighted as: • of interest

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