The Selective Serotonin Reuptake Inhibitors (SSRIs) act on a serotoninergic system. Serotonin is involved in mood regulation, however it also plays a role in digestion, pain, sleep, mental clarity, and other bodily functions. As a result, the SSRI antidepressants cause a wide range of side effects. It was reported that in some cases, a high serum concentration of citalopram in elderly patients has been associated with increased somnolence and movement difficulties but not with delirium.

We report the case of a 65-years-old depressive man in whom i.v. citalopram in monotherapy induced delirium.

Our patient was admitted to a closed geriatric ward as a psychotically depressed with somatic and depressive delusions and suicidal thoughts. Because he rejected all per os drugs we started only with citalopram i.v. (1 ampoule of citalopram in 500 ml NS) and after 3 days he became delirious and physically aggressive because of what he was restrained. We stopped citalopram. Next day he was alert and oriented, there was no evidence of psychotic symptoms, hallucinations, or delusions. Patient was euthymic. He was not suicidal at the time of evaluation. In few days he became depressed again with depressive and nihilistic delusions. We started with dual-acting antidepressant and atypical antipsychotic what led to remission. Depressive episodes were not observed in four-year follow up.

In this report, we described a patient with acute hyperkinetic delirium associated with a i.v. citalopram what is the first description of this kind of sideects of i.v. citalopram.