An inhibitor of serotonin (5-HT) uptake. Antidepressant.;(R)-Citalopram Oxalate is a derivative of Citalopram. Citalopram is a selective inhibitor of the 5-hydroxytryptamine transporter (serotonin) and therefore is a potent and selective serotonin reuptake inhibitor. Additional studies in indicate that Citalopram may be a weak, allosteric modulator of serotonin in a cross-species chimeric study. Studies also indicate that Citalopram is useful for studying gene expression patterns in circulating lymphocytes. In zebrafish, Citalopram is noted to reduce the frequency of NMDA-induced locomotor rhythm involved in swimming behavor.