Psychosis induced by antidepressant treatment with reboxetine

To the Editor

Despite the growing body of literature reporting relationships between selective serotonin reuptake inhibitors (SSRIs) and psychosis, less has been written about the relationship between norepinephrine reuptake inhibitors (NaRIs) and psychosis, in particular the drug reboxetine, with reports of neuropsychiatric manifestations being scant. While reboxetine has been associated with adverse effects such as insomnia, agitation and anxiety (Home – electronic Medicines Compendium [eMC], 2019; Whiskey and Taylor, 2013), a literature search revealed no cases of reboxetine use precipitating psychotic episodes.

Here we report the case of a high functioning 51-year-old woman (Ms. M) who presented with a 3-month history of delusional, intrusive thoughts in the context of a medication change from venlafaxine to reboxetine. On assessment, the patient reported an ongoing delusion of grandeur that she would give birth to an important world leader and ideas of reference such as attributing special meaning to people’s hand signals. Cognition was intact. She recounted a similar sudden-onset, brief episode of psychosis 3 years ago – again in the context of using the NaRI reboxetine, which was responsive to very low dose antipsychotic medication risperidone. Reboxetine was not identified as a causal factor in either of these two psychosis episodes and Ms. M was treated with low dose risperidone on both occasions. To treat this current psychosis, we ceased her reboxetine and her psychosis symptoms had completely resolved 1 week later. We also slowly titrated down the antipsychotic medication, and on review, 6 months after the second episode of psychosis, Ms. M remains very well.

The case above presents an unusual onset of psychosis symptoms, indicative of organic mental illness, in this case, due to an unusual response to the NaRI antidepressant – reboxetine. Additional research is required to ascertain if a causal relationship exists with reboxetine use precipitating episodes of psychosis.