The investigation of time dependent alterations in the pharmacokinetics, therapeutic effect and adverse effects in patients with major depressive disorder treated with venlafaxine

The aims of the study are to investigate: (1) the pharmacokinetic properties and therapeutic effect of venlafaxine (2) the possible relationship between the plasma concentration of venlafaxine and the clinical outcome and the frequency of adverse effects, according to the time of administration.In this study 13 major depression patients have been studied. Plasma concentrations of venlafaxine were measured by HPLC, the therapeutic response to venlafaxine was determined by MADRS and CGI; adverse effects were evaluated by UKU side effect scale.There is no statistically significant difference in Cmax, Tmax and AUC values in patients with major depressive disorder who are treated with venlafaxine either in the morning or evening.Our findings showed that there is no statistically significant difference among the patients responding and non-responding to drug theraphy and patients in whom adverse reactions were and were not observed with respect to AUC and Cmax of venlafaxine administrated either in the morning or evening.Although there?s a few number of preliminary data, we think that both morning and evening administration of venlafaxine are effective and safe in the treatment of major depression. Both options may be prescribed according to patient - physician?s decision.