RABBIT SYNDROME INDUCED BY ATYPICAL ANTIPSYCHOTICS: A RARE EXTRAPYRMIDAL SIDE EFFECT

Abstract

Rabbit syndrome (RS) characterized by rapid, fine, rhythmic movements of the perioral muscles along a vertical axis at a frequency of about 5 Hz, mimicking the chewing and puckering movements of a rabbit with no Rabbit syndrome (RS) is a rare extra pyramidal symptom (EPS) caused by a prolonged neuroleptic medication, RS is characterized by rapid, fine, and rhythmic movements with the involvement of the tongue. Patients using antipsychotics found to have a rabbit syndrome prevalence that ranges from 1.3 to 4.4%. Polypharmacy and long-term neuroleptic use are the risk factors in developing this syndrome. RS is typically thought to be caused by first-generation antipsychotics. Nonetheless, second-generation antipsychotics like Riserpidone, which have a strong serotonin blockade and a lessened dopaminergic blockade also causes RS more frequently. Differential diagnosis include tardive dyskinesia in which movements are slow and irregular which does not follow rhythmicity and involves tongue movement. Management usually involves the reduction in the dose or changing to alternative atypical antipsychotics. Anticholinergics and anti-parkinsonic medications are also helpful to treat RS.