An Organic Psychosis Due to a Venlafaxine-Propafenone Interaction

Objective: An extraordinary case of an organic psychosis during the treatment of a patient with a bipolar affective disorder. Methods: Clinical observation and further investigations including monitoring of serum levels (case report). Results: A significant interaction between venlafaxine and propafenone causes markedly increased serum levels of venlafaxine correlating with unexpected psychopathological changes. Conclusions: There is a potentially dangerous interaction between venlafaxine and propafenone. Serum levels of venlafaxine should be monitored if propafenone is added.