Drug-induced and psychogenic resting suprahyoid neck and tongue tremors.

We describe three patients who presented with 4 to 5 Hz tremors of the suprahyoid region of the neck. Two developed their tremors in association with levosulpiride treatment. When they opened their mouths, the neck tremors disappeared; no tongue tremors were observed. However, a videofluoroscopic examination showed the presence of tongue tremors at rest. The remaining patient had a psychogenic tremor.