Es la prolactina un biomarcador útil para la dosificación de risperidona

Introduction. Prolactin is considered as a useful biomarker of dopaminergic response in treatments with haloperidol. In the case of risperidone, where the elevation of prolactin is consistent and durable, additional data are required for its validation as a biomarker. Objectives. The aim of this study was to validate the use of prolactin as a therapeutic biomarker in patients treated with risperidone parenteral. Material and methods. Prospective study over 30 patients for the construction of the dose-response relationship between dose of RISPERDAL CONSTA® and its serum prolactin level. CYP2D6 genotyping was carried out by PHARMAchip ® test. Results. Dose-response curve type PRL = 84D2/90 + D2    (PRL = prolactinemy.  D = Dosis/14 days), r2 = 0.71. Two patients, 6.6% of the sample, had a CYP2D6 genotype (*4/*4). Discussion. From the dose-response data and clinical observation, we have defined as infratherapeutic treatments those where prolactinemy was lower than 35-40 ng / ml (20-25 for men) and potentially iatrogenic those others that prolactinemy exceeded 70-84 ng / ml (35-40 in males). Patients who had a genotype “poor metabolizer” (6.6%), 2 patients with CYP2D6 (*4/*4), had a clearance of the active fraction of risperidone less than 2.2 times that individuals with “extensive metabolizer” genotype.