Low dose of clozapine in the treatment of dopaminergic psychosis in Parkinson's disease.

Dopaminergic psychosis frequently complicates the pharmacological treatment of Parkinson's disease. Dose reduction of dopaminomimetic therapy or treatment with conventional neuroleptics improves psychosis but worsens parkinsonism. In an open-label 12-month trial, the clinical antipsychotic efficacy of the atypical neuroleptic clozapine was investigated in 36 parkinsonian patients (age range 46-85 years) with symptoms of dopaminergic psychosis including delusions, vivid dreams, hallucinations, frank paranoid delirium, and hypersexuality.

Motor fluctuations in levodopa treatment: clinical pharmacology.

Fluctuations in motor performance and dyskinesias are a common problem in the long-term management of Parkinson's disease. The pharmacokinetics and the pharmacodynamics of levodopa, loss of presynaptic dopamine terminals, alterations in postsynaptic dopamine receptor sensitivity, or changes in the modulatory influences of nondopaminergic transmitter system could play a pathogenic role. The short half-life of levodopa and its absorption and transport are important factors.

The clinical efficacy of a single afternoon dose of levodopa methyl ester: a double-blind cross-over study versus placebo.

Levodopa methyl ester (LDME) is a highly water soluble derivative produced by esterification of the carboxilic acid moiety of the L-Dopa molecule that is rapidly hydrolyzed to L-Dopa and can be administered orally in an easily dosable liquid form. In this study the relative efficacy and tolerability of a single dose of an oral solution of 250 mg of LDME was compared to that of placebo in reversing afternoon off period. A controlled double-blind cross-over study versus placebo had previously been carried out in 25 idiopathic parkinsonian patients with predictable fluctuations in motor performances.

Clinical implications of sustained dopaminergic stimulation.

Fluctuations in motor performance are the major problems in chronic management of Parkinson's disease. Most of these fluctuations reflect the decline of levodopa availability. As a consequence, levodopa dosage might be increased and the interdose interval progressively shortened.

[Changes in the nigrostriatal dopamine receptor compartment after continuous dopaminergic infusions in Parkinson disease].

Motor fluctuations often complicate chronic levodopa treatment of Parkinson's disease. Pharmacologically, these phenomena are characterized by a progressive shortening of the duration of action of levodopa and a gradual narrowing of the range of "optimally effective" doses, able to improve parkinsonian akinesia without inducing abnormal involuntary movements. The effects of a continuous intravenous infusion of levodopa lasting 9 +/- 0.