Levodopa remains a 'gold standard' for the treatment of patients with Parkinson's disease (PD), but its chronic use is accompanied by fluctuations of symptoms and dyskinesias related to unfavorable pharmacokinetics of levodopa and progressing loss of the nigrostriatal neurons. Prescribing inhibitors of catechol-O-methyl-transferase (enzyme of dopamine metabolism), entacapone or tolcapone, is a perspective approach to the correction of the above-mentioned complications. We followed up 402 patients with PD who received long-term therapy with a combined preparation Stalevo (levodopa/carbidopa/entacapone) for 2-5 years (2.9±0.9 years). The high (92.8%) compliancy and good tolerance of the drug in patients with PD was shown. Stalevo leads to the stabilization of the response to levodopa, improvement of patients' functional capacities, increase in their everyday activity, and improvement of quality of life. Stalevo may be regarded as a preparation of choice in the treatment of motor complications in elderly patients, correction of night symptoms of PD and in a number of other clinical situations arising in hospital and outpatient practice.