OBJECTIVES Entacapone is a specific, potent, peripherally acting catechol-O-methyltransferase (COMT) inhibitor. It has been shown to improve the bioavailability of plasma levodopa and extend its clinical effect when used as an adjunct to standard levodopa preparations, but there is little experience of the effect of entacapone on controlled release levodopa preparations. METHODS A double blin...

A new layered organic-inorganic nanocomposite material with an anti-parkinsonian active compound, L-3-(3,4-dihydroxyphenyl) alanine (levodopa), intercalated into the inorganic interlayers of a Zn/Al-layered double hydroxide (LDH) was synthesized using a direct coprecipitation method. The resulting nanocomposite was composed of the organic moiety, levodopa, sandwiched between Zn/Al-LDH inorganic...

The studies of duodenal infusion of a levodopa on small groups of parkinsonian patients have reported beneficial effects on motor complications. However, little is known about the patient profile and indications for duodenal levodopa infusion. The purpose of this study is to exhaustively investigate the clinical characteristics of the population and indication, efficacy and tolerability of duod...

Treatment of patients with Parkinson's disease with levodopa has profound effects on both movement and the pattern of movement-related reactivity in the subthalamic nucleus (STN), as reflected in the local field potential (LFP). The most striking change is the promotion of reactivity in the gamma frequency band, but it remains unclear whether the latter is itself a pathological feature, possibl...

Parkinson disease is an age-related disorder of the central nervous system principally due to loss of dopamine-producing cells in the midbrain. Levodopa, in combination with carbidopa, is widely regarded as an effective treatment for the symptoms of Parkinson disease. A dose-response relationship is established for carbidopa-levodopa extended-release capsules (IPX066) in levodopa-naive Parkinso...

BACKGROUND The effect of initiation of levodopa therapy on the memory functions in patients with Parkinson's disease remains poorly understood. AIMS To evaluate the effect of initiation of levodopa therapy on memory, in patients with early Parkinson's disease. SETTINGS AND DESIGN Prospective case control study. MATERIALS AND METHODS Seventeen patients with early Parkinson's disease were e...

Early treatment of Parkinson's disease (PD) affords an opportunity to forestall clinical progression. Levodopa is the most effective treatment for PD motor signs and symptoms, but its use is associated with the development of motor fluctuations and dyskinesias. Because of this, levodopa use is commonly withheld until the patient experiences functional disability. Other medications are available...

AIMS Resting tremor in Parkinson's disease (PD) increases markedly during cognitive stress. Dopamine depletion in the basal ganglia is involved in the pathophysiology of resting tremor, but it is unclear whether this contribution is altered under cognitive stress. We test the hypothesis that cognitive stress modulates the levodopa effect on resting tremor. METHODS Tremulous PD patients (n = 6...

Patients with Parkinson disease often have orthostatic hypotension. Neurocirculatory abnormalities underlying orthostatic hypotension might reflect levodopa treatment. Sixty-six Parkinson disease patients (36 with orthostatic hypotension, 15 off and 21 on levodopa; 30 without orthostatic hypotension) had tests of reflexive cardiovagal gain (decrease in interbeat interval per unit decrease in sy...