A 33-year-old male with diphasic
dyskinesia was presented. He began to have difficulty with walking at the age of 27, and was diagnosed to have
juvenile parkinsonism. For the past two years,
L-dopa has been prescribed with good initial response. One year ago peripheral
dopa decarboxylase inhibitor in combination with
L-dopa was started, and he began to have
involuntary movements. One hour after taking 2
tablets of EC
dopa (
L-dopa 100 mg +
benserazide 25 mg), violent involuntary ballistic movements appeared in all four extremities which lasted for 15 minutes. For the following 50 minutes, his symptoms of
parkinsonism markedly improved. The score of
parkinsonism reduced by 58%, and he was able to walk. The plasma
dopa level was increasing during this period. However, during decreasing period of plasma
dopa concentration, he did not have end-of-dose
dyskinesia. On the other hand, one hour after taking 500 mg of
L-dopa involuntary
choreic movements appeared in his right upper extremity for several minutes without any improvement of
parkinsonism. Three hours and 20 minutes after taking
L-dopa, he developed mild
choreic movements for several minutes followed by marked improvement of
parkinsonism for 30 minutes. The score of
parkinsonism reduced by 79%. Thirty minutes later, he developed violent ballistic movements in all four extremities, lasting for 30 minutes followed by reappearance of
parkinsonism. The concentration of plasma
dopa was decreasing during this period.(ABSTRACT TRUNCATED AT 250 WORDS)