Zeruesenay Desta

TL;DR: Interactions between CYP2D6 polymorphisms and coadministered antidepressants and other drugs that are CYP 2D6 inhibitors may be associated with altered tamoxifen activity.

TL;DR: Genotyping for the common alleles of CYP2C19 before initiating PPIs for the treatment of reflux disease and H. pylori infection is a cost effective tool to determine appropriate duration of treatment and dosage regimens and, because of its narrow therapeutic range, genotyping of CYPs in addition to CYP1C9 may be needed to optimise the dosage of phenytoin.

TL;DR: The data suggest that CYP2D6 genotype and drug interactions should be considered in women treated with tamoxifen, and the metabolite 4-hydroxy-N-desmethyl-tamox ifen is an active tamoxIFen metabolite that is generated via CYP3A4-mediated N-demethylation and CYP 2D6-mediated hydroxylation.

TL;DR: In tamoxifen-treated patients, women with the CYP2D6 *4/*4 genotype tend to have a higher risk of disease relapse and a lower incidence of hot flashes, which is consistent with the previous observation that CYP3A5*3 variant was not associated with any of these clinical outcomes.

TL;DR: Variable activity of these P450s, brought about by genetic polymorphisms and drug interactions, may alter the balance of TAM effects in vivo.