The precise estimation of the drug metabolism capacity of patients is essential when it comes to the administration of the right personalized dose. This study aims to define the difference in the antidepressant and antipsychotic exposure among patients with genetically associated CYP2C19 and CYP2D6 poor (PM), intermediate (IM), and normal (NM) metabolizers.

 This systematic review and meta-analysis included a total of 94 unique studies that included a total of 8,378 individuals. The studies included in the analysis had CYP2C19 or CYP2D6 genotyping or a possible genotype-based classification into CYP2C19 or CYP2D6 NM, IM, and PM. The primary outcome of the study was drug exposure.

 The findings suggested that patients who were treated with aripiprazole, haloperidol lactate, risperidone, escitalopram oxalate, and sertraline hydrochloride demonstrated the most profound difference. In addition, exposure differences were observed for clozapine, quetiapine fumarate, mirtazapine, amitriptyline hydrochloride, fluoxetine hydrochloride, nortriptyline hydrochloride, paroxetine hydrochloride, fluvoxamine maleate, and venlafaxine hydrochloride. However, these differences were ambiguous or marginal and weren’t statistically significant.

 This systematic review and meta-analysis concluded that the association between CYP2C19 and CYP2D6 genotypes and the drug levels of numerous antidepressant and antipsychotic drugs was quantified with high precision. However, some drugs lacked precision, and more data is required to derive statistically significant associations.

 Ref: https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2773579?resultClick=1

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