Citalopram – what you need to know about this proven antidepressant

Abstract

Citalopram is an antidepressant belonging to the group of selective serotonin reuptake inhibitors, a racemate consisting of two enantiomers: R-citalopram and S-citalopram, which show different pharmacological properties. The receptor binding profile of citalopram results from the different mechanisms of action of these two enantiomers: S-citalopram inhibits serotonin reuptake on the presynaptic neuron, whereas R-citalopram is a mild antihistamine, blocking the histamine H1 receptor. Over the years, citalopram has proven to be an effective antidepressant. Compared to other agents in this group, it involves a low risk of interactions, which is due to its low potential to inhibit CYP450 enzymes and lower binding affinity to serum proteins (below 80%) compared to other antidepressants. The drug poses no cardiac risk when given at standard, registered doses. The risk of prolonged QTc occurs at elevated levels of a metabolite didemethylcitalopram (DDCT). This may occur in 2% of patients with genetically variable CYP450 2D6 metabolism as well as in patients receiving CYP450 2C19 inhibitors. Due to these properties, citalopram may be useful in both young and older patients as well as those using polytherapy for multiple somatic comorbidities. The receptor binding profile of the drug allows targeting specific psychosomatic symptoms for which the drug is likely to be most effective. It seems that depressive patients with dominant psychopathological symptoms, such as increased anxiety, agitation, irritability, impulsiveness and sleeping disorders, are likely to benefit most from this drug.

Keywords

• antidepressants
• citalopram
• depression
• interactions