항파킨손약물로 치료한 토끼증후군 1례

A Case of Rabbit Syndrome Treated with Antiparkinsonian Drug

Rabbit syndrome is a perioral involuntary, extrapyramidal movement disturbance associated with prolonged use of neuroleptics. The disturbance involves the oral and masticatory musculature except for the tongue; it is similar in appearance to the movements of a rabbit’s mouth. Quickly alternating, regular movements along a vertical axis occur at a frequency of approximately 5 Hz. Differential diagnosis between tardive dyskinesia and rabbit syndrome is often confused; tardive dyskinesia also can involve orofacial musculature but is manifested by chewing-like movements that include writhing or thrusting tongue motions. Differentiation between the two conditions is made clinically. Abnormal movements in tardive dyskinesia is significantly slower and less regular than in rabbit syndrome. Although both disorders are sequelae of longterm neuroleptic treatment, rabbit syndrome responds to antiparkinsonism medications, while tardive dyskinesia is often exacerbated by such therapy.