Abstract: Objective To observe the effect of catechol-O-methyltransferase inhibitor (COMTI) tolcapone on levodopa-treated patients with Parkinson's disease (PD) and on the motor function fluctuation, and safety taking this drug.Methods50 PD patients treated with levodopa were divided into the trial group and control group with 25 cases in each group. The patients in the trial group were given tolcapone 100 mg three times per day. The cases in the control group were given placebo with the same dose. The hepatic function of the patients was examined every month after administration. The time variety of patients' motor function fluctuation was recorded by the diary. The time of clinical observation was 6 months.ResultsThe UPDRS scores of the trial group in the first and second months after taking tolcapone were not significantly different from that of the control group ( P>0.05), but scores of the third to sixth months were significantly different from that of the control group ( P<0.05～0.01). There was a significant difference between UPDRS scores of the trial group before and after treatment ( P<0.01～0.001). The Honhe-Yahr scores of the trial group in the first and second months after treatment were not significantly different from that before treatment ( P>0.05), but scores of the third to sixth months were significantly different from that before treatment ( P<0.05). The motor function fluctuation of the patients in the trial group improved significantly after treatment ( P<0.05). The numbers of the cases had dry mouth, nausea and astriction were 3 respectively; those had acratia, insomnia and diarrhea were 2 respectively; those had muscular soreness, abdominal distention, hidrosis and fidget were 1 respectively. All adverse effects had a little influence to administration. The hepatic function of all patients had no significant change.ConclusionTolcapone can increase the curative effect of PD patients treated with levodopa and improve the motor function fluctuation, and is safety after taken.

Key words: Parkinson's disease, levodopa, tolcapone