Pramipexole-induced antecollis in patients with Parkinson's disease: Two cases and literature review.

Antecollis is considered to be relatively rare in Parkinson's disease (PD). Few cases of dopamine agonist-induce antecollis in PD have been reported. We described literature review of 12 PD patients including our 2 cases with pramipexole (PPX)-induced antecollis. The patients were predominantly Japanese, women and above 3 of Hoehn and Yahr stage. PPX-induced antecollis in PD was considered a type of dystonia of flexor neck muscle, and was improved soon after cessation or reduction of PPX. Our two cases improved their antecollis by overnight changing from PPX to ropinirole without deteriorating motor functions. Overnight switching of DA was considered useful as one option in the treatment of antecollis.