This article includes Supplementary Video, available online at .

jws-mds.20473.vid.mpg13608K Segment 1. Details of the focal dyskinesia, which is limited to the lower lip, are demonstrated. The dyskinesia consists of tonic and sustained outward protrusion of the lip to the right side. Intermittent bursts of clonic twitching are seen involving the affected part. Pursing the lips as in whistling could suppress the dyskinesia only marginally. Segment 2. Recorded after 2 days of oral phenytoin therapy. The dyskinesia has disappeared completely. This video presentation has been abbreviated. The full version will appear on theMovementDisorders DVD Supplement, which is issued bi-annually.

Please note: Wiley Blackwell is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.