title: Venlafaxine: the relationship between dose, plasma concentration and clinical response in depressive patients.
abstract: The relationship between plasma drug level of venlafaxine and daily intake was studied in 89 major depressive inpatients. In addition, changes over time in severity were assessed weekly in a subgroup of 22 depressed patients using the Montgomery and Asberg Depression Rating Scale (MADRS) and the Clinical Global Impression improvement scale. The results indicate a moderate correlation between daily doses and plasma concentrations, together with a higher relationship between improvement on the MADRS scale and concentration. Moreover, plasma concentrations (for venlafaxine and its predominant metabolite, O-desmethylvenlafaxine) up to 400 microg/l can be considered as effective, as already suggested in a previous study. No case of venlafaxine discontinuation occurred during the longitudinal study, and the incidence of adverse event, as estimated by the Target Emergent Symptoms and Side-effects scale, was low, suggesting that the drug is well tolerated for such plasma concentrations.
authors.affiliation: University of Liège, Toxicology Laboratory, CHU Sart Tilman, Liège, Belgium. c.charlier@chu.ulg.ac.be
authors.forename: C
authors.initials: C
authors.lastname: Charlier
authors.forename: E
authors.initials: E
authors.lastname: Pinto
authors.forename: M
authors.initials: M
authors.lastname: Ansseau
authors.forename: G
authors.initials: G
authors.lastname: Plomteux
mesh_terms: D000328:Adult; D000368:Aged; D018687:Antidepressive Agents, Second-Generation / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use*; D001711:Biotransformation; D003511:Cyclohexanols / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000523:psychology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D000069470:Venlafaxine Hydrochloride
chemical_list: D018687:Antidepressive Agents, Second-Generation; D003511:Cyclohexanols; D000069470:Venlafaxine Hydrochloride