Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tolcapone, a central and peripheral catechol O-methyltransferase (COMT) inhibitor, reduces the conversion of L-Dopa into 3-O-methyl-Dopa (3-OMD), thus leading to more stable and sustained L-Dopa plasma levels. This study was designed to evaluate the effects of acute and 6-week tolcapone administration on L-Dopa pharmacokinetics and pharmacodynamics in Parkinson's disease (PD) patients with predictable motor fluctuations. Tapping test, walking time, and tremor, as well as L-Dopa and 3-OMD plasma levels, were assessed before and for 5 hours after the administration of a single L-Dopa dose, alone or in combination with 200 mg tolcapone, in seven patients with PD. This clinical and pharmacokinetic study was repeated after 6 weeks of tolcapone therapy (200 mg three times daily). It was observed that tolcapone, after both acute and chronic administration, prolonged the motor improvement induced by L-Dopa. As a result, at week 6 of tolcapone therapy, the daily hours spent "off" were significantly decreased. Tolcapone significantly increased the area under the curve of L-Dopa plasma levels by slowing down the elimination of L-Dopa from plasma, whereas the maximal concentration of L-Dopa was not modified. 3-OMD levels decreased significantly after acute tolcapone administration, and after 6 weeks of tolcapone therapy, they were approximately one sixth of pre-tolcapone values. The data confirm that tolcapone decreases L-Dopa clearance and prolongs motor response in PD patients with motor fluctuations, and that this effect is maintained after 6 weeks of tolcapone therapy.
 ...
PMID:Pharmacokinetics and pharmacodynamics of L-Dopa after acute and 6-week tolcapone administration in patients with Parkinson's disease. 1004 30

The aim of the study was to investigate the efficacy of homemade tolcapone in treatment of patients with Parkinson's disease (PD). Eighty patients with PD were subjected to randomized, double-blind, placebo-controlled and parallel-group study. PD patients were randomly divided into the tolcapone treatment group (41 cases) and placebo group (39 cases). Each patient received 1 pill of tolcapone or placebo, 3 times per day for 26 weeks. Efficacy was evaluated using the internationally used unified Parkinson's disease rating scale (UPDRS) scoring system for PD symptoms. After the treatment for 26 weeks, the cognitive function, tremor, muscle stiffness, voluntary movement and autonomic nerve symptoms were compared between the two groups using UPDRS scores. Compared with the placebo group, cognitive function, muscle stiffness and voluntary movement reduction were significantly improved in patients of the tolcapone group (P<0.05). However, no significant differences in UPDRS scores of autonomic nerve symptoms and tremor were found between two groups after treatment (P>0.05). Tolcapone, a catechol-O-methyl transferase (COMT) inhibitor, can improve the motor function of patients with PD, especially exercise and muscle stiffness. Tolcapone can also improve the cognitive function of patients.
 ...
PMID:The efficacy of homemade tolcapone in the treatment of patients with Parkinsons disease. 2937 79