Amantadine may reverse punding in Parkinson's disease--observation in a patient.

Punding, complex stereotyped behavior, sometimes occurs in patients with Parkinson's disease under dopaminergic replacement therapy. Reduction of dopaminergic drugs may reduce the problem but risks enhancing motor impairment. We report a patient with Parkinson's disease presenting disabling punding, which was reversed by amantadine without aggravating motor function. Amantadine may reduce punding by blocking NMDA receptors, in the same manner as in levodopa-induced dyskinesias.