Case report: Therapeutic drug monitoring and CYP2D6 phenoconversion in a protracted paroxetine intoxication.

Objective: The cytochrome P450 2D6 (CYP2D6) is an enzyme involved in the oxidative biotransformation of various widely used drugs, including paroxetine, a substrate and strong inhibitor of the enzyme. The aim is to report on a case of protracted intoxication with paroxetine after a single overdose in a genotype-predicted intermediate CYP2D6 metabolizer.

Observation: A 49-year-old man was receiving chronic treatment for more than 6 years with paroxetine 60 mg/day for an indication of agoraphobia.

MDR1 in paroxetine-induced sexual dysfunction.

Paroxetine-induced sexual dysfunction represents a frequent treatment complication of otherwise efficient antidepressants. The genetic polymorphism of pharmacokinetic genes may contribute to the occurrence of such dysfunctions. This study presents the effect of MDR1 gene polymorphisms on sexual function in 18 women with bulimia nervosa, 18 women with anxiety disorders, and 19 healthy control subjects.

Relevance of CYP2D6 variability in first-episode schizophrenia patients treated with risperidone.

Objective: The objective of this prospective, naturalistic study, conducted in first-episode psychosis patients from a Central-European population, was to assess the utility of Cytochrome P-450 2D6 (CYP2D6) genotype testing under normal clinical setting.

Methods: A total of 35 patients diagnosed for the first time with schizophrenia or acute schizophrenia-like psychotic disorder and treated with risperidone were enrolled in the study. These patients underwent sequentiation of the CYP2D6 gene and evaluations of symptoms and severity of adverse effects using the PANSS and UKU scales, respectively.