Rabbit syndrome: Developed after increasing the dosage of quetiapine in a patient using quetiapine with duloxetine

摘要

Fifty-six years old, female patient who was being followed and treated for resistant depression, had been using duloxetine 60 mg/day and quetiapine 300 mg/day for 3 months. After 2 weeks the quetiapine dose was increased to 600 mg/day because of resistant depression concomitant with insomnia. A movement disorder was observed, appearing as a rhythmic tremor in the perioral muscles which was defined by the patient as involuntary. This involuntary rhythmic perioral tremor was diagnosed as rabbit syndrome and for this reason quetiapine, the only antipsychotic used by the patient, was gradually decrease in dose and eventually stopped. Four weeks after stopping the quetiapine, the patient’s involuntary perioral rhythmic movements decreased from four to zero points, according to the lips and perioral subgroup of the Abnormal Involuntary Movements Scale (AIMS).