Atypical antipsychotic-induced rabbit syndrome: A rare adverse drug reaction

Abstract: Rabbit Syndrome (RS) is a rare extrapyramidal side effect characterized by rhythmic, vertical, perioral movements that resemble the chewing motion of a rabbit. It is typically associated with long-term use of first-generation (typical) antipsychotics but has been occasionally reported with second-generation (atypical) agents. RS can often be misdiagnosed as tardive dyskinesia due to overlapping symptoms, though the absence of tongue involvement distinguishes it. This report presents a rare case of RS following the use of olanzapine and quetiapine – two atypical antipsychotics. As part of a pharmacovigilance elective conducted under the Department of Pharmacology, Christian Medical College, Ludhiana (an adverse drug reactions Monitoring Center), a case was collected from the Department of Psychiatry. This case highlights a rare but important adverse drug reaction associated with atypical antipsychotics. Given the limited number of reported RS cases with olanzapine and quetiapine – despite their widespread use – this report underscores the need for increased awareness and vigilance among clinicians. Early recognition and appropriate management are essential for symptom resolution and prevention of misdiagnosis.