NeuroTeach 30 - Rabbit syndrome

Rabbit syndrome!!!

“a peculiar extrapyramidal reaction”

Canadian psychiatrist André Villeneuve 1972, the first report

2) Definition

“stereotyped vertical, rhythmic movements, similar to the chewing movements of a rabbit” 5 Hz Lips produce a popping sound Not tardive dyskinesia! - persist stage I sleep

3) Pathophysiology

- cholinergic system?

4) Clinical tips

dyskinesia versus rabbit syndrome i) tongue 10s extruded - dyskinesia, tongue twist - rabbit, no movement ii) lips movement - only vertical, rabbit syndrome - all directions, dyskinesia iii) movement pace - fast & rhythmic, rabbit - slower & irreg, dyskinesia

5) Management

Long-term antipsychotic use, begins a few days after modification in psych treatment Disappear after antipsychotic discontinuation - anti-Parkinson's drugs, some

6) Rabbit syndrome

💡after risperidone withdrawal

7) Rabbit syndrome

💡amisulpride-induced

8) Rabbit syndrome

💡paliperidone discontinuation

9) Rabbit syndrome

💡functional

10) Differ

perioral & pharyngeal myorhythmia - lower freq (1-4 Hz), when compared to rabbit syndrome

11) Differ

tardive dyskinesia -🔄& irregular

12) Differ

perioral myorhythmia - lower freq (1-4 Hz), when compared to rabbit syndrome 💡medullary compression by vertebral artery

13) Differ

perioral myorhythmia - lower freq (1-4 Hz), when compared to rabbit syndrome 💡EMG should be performed

14) Differ

hereditary chin trembling (geniospasm) 💡childhood 💡improve w/ aging

💡botox-sensitive