Psychotic treatment-resistant depression is a severe form of major depressive disorder involving hallucinations or delusions, often underdiagnosed and undertreated. Ketamine has shown rapid antidepressant effects, and its enantiomer esketamine was approved for treatment-resistant depression in 2019. This report describes four inpatients with treatment-resistant depression and psychotic features, including one in severe suicidal crisis, who received a single 0.5 mg/kg intravenous infusion of ketamine as an add-on to standard care. Monitoring showed no worsening of psychotic symptoms in short or long term, and all patients achieved stable remission with an immediate antisuicidal effect. Ketamine may benefit individuals with this condition.
Low-dose intravenous ketamine was safe and well tolerated in six patients with both depression and epilepsy. Side effects were mild and temporary, and no worsening of seizures occurred. Four of the six patients showed a significant reduction in depression scores on the Montgomery-Åsberg Depression Rating Scale, with two achieving full remission. Three patients reported a subjective decrease in seizure activity over twelve months. No serious adverse events happened. The authors caution that this is a small, post-hoc observation and that larger prospective studies are needed to confirm effects on seizures, depression, and side effects.