Progressive dystonia with marked diurnal fluctuation.

Two cases of dopa-responsive dystonia with marked diurnal fluctuations are reported. Of these, one was a 26 year old female who had progressive dystonia of more than 20 years' duration with classical diurnal fluctuations exacerbated by exercise and relieved with sleep; she also had significant worsening during menstruation and the later half of her pregnancy, resulting in a stillbirth. She responded remarkably to low doses of L-dopa.