Efficacy and tolerability of escitalopram versus citalopram in major depressive disorder: a 6-week, multicenter, prospective, randomized, double-blind, active-controlled study in adult outpatients.

Background: The S-enantiomer of citalopram (escitalopram) is the active moiety linked to the anti-depressant effects associated with citalopram (the racemate). For escitalopram to be approved for the treatment of depression in Europe, findings from clinical trials of escitalopram are required to match previous results from studies of the racemate, citalopram.

Objective: The aim of this study was to compare the efficacy and tolerability of escitalopram and citalopram in outpatients with major depressive disorder (MDD).