The Sequenced Treatment Alternatives to Relieve Depression sample was used to examine the relationship between variations in the CYP2C19 and CYP2D6 genes and remission of depressive symptoms and tolerance to treatment with citalopram.
Genetic tests suitable for the routine laboratory are now available for some important metabolizing enzymes (e.g., CYP2D6, CYP2C19) identifying those individuals who are slow or fast metabolizers of certain drugs, many of which are widely used in the treatment of depression (e.g., tricyclic antidepressants).
We evaluated whether cytochrome P450 (CYP) poor metabolizer polymorphisms of CYP2D6 and CYP2C19 are relevant for the outcome (measured by length of hospitalization) during treatment with psychotropic medications in patients with depression or schizophrenia.
We report the effect of CYP2C19 and CYP2D6 genotypes on steady state morning concentrations of escitalopram and N-desmethylescitalopram and the ratio of this metabolite to the parent drug in 196 adult patients with depression in GENDEP, a clinical pharmacogenomic trial.