Glutamate release inhibition ineffective in Levodopa-induced motor complications

Reported benefits of various glutamatergic receptor antagonists in Parkinson's disease (PD) prompted an evaluation of the antidyskinetic effect of a putative glutamate release inhibitor in 15 moderately advanced patients. In a 3-week, double-blind, proof-of-concept study, riluzole (200 mg/day) failed to alter parkinsonian or levodopa-induced motor complication severity. Opposing effects of a generalized inhibition of glutamate-mediated synaptic transmission may limit the usefulness of this approach to treat PD.