Atypical extrapyramidal manifestation of a typical antipsychotic with serotonergic antidepressant

Abstract

Introduction: Typical antipsychotics are known to produce extrapyramidal side effects such as drug induced parkinsonism, acute dystonia, akathisia, tardive dyskinesias and rabbit syndrome. Rabbit syndrome is characterized by vertical rhythmic motion of the mouth and lips, resembling chewing movements of a rabbit. Reason for the report: Rabbit syndrome seen in patients on antidopaminergic therapies is characterized by vertical rhythmic movements of perioral region, has a late onset, and characteristically spares the tongue. The main aim of the report is to highlight atypical manifestation of antipsychotic associated Rabbit syndrome in the presence of a serotonergic antidepressant. Case summary: An elderly patient presented with atypical rabbit syndrome with relatively acute onset, horizontal movements of jaw and marked tongue involvement after haloperidol-escitalopram initiation. Outcome: The patient improved with discontinuation of antipsychotic. The tongue involvement was believed to be secondary to escitalopram use. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Tehran University of Medical Sciences 2023.