Differences in the dynamics of serotonin reuptake transporter occupancy may explain superior clinical efficacy of escitalopram versus citalopram

@article{Kasper2009DifferencesIT,
  title={Differences in the dynamics of serotonin reuptake transporter occupancy may explain superior clinical efficacy of escitalopram versus citalopram},
  author={Siegfried Kasper and Julia Sacher and Nikolas Klein and Nilufar Mossaheb and Trawat Attarbaschi-Steiner and Rupert Lanzenberger and Christoph Spindelegger and Susanne Asenbaum and Alexander Holik and Robert Dudczak},
  journal={International Clinical Psychopharmacology},
  year={2009},
  volume={24},
  pages={119-125}
}
Escitalopram the S-enantiomer of the racemate citalopram, is clinically more effective than citalopram in the treatment of major depressive disorder. However, the precise mechanism by which escitalopram achieves superiority over citalopram is yet to be determined. It has been hypothesized that the therapeutically inactive R-enantiomer competes with the serotonin-enhancing S-enantiomer at a low-affinity allosteric site on serotonin reuptake transporters (SERTs), and reduces the effectiveness of… 
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