Rivastigmine: in Parkinson's disease dementia.

Rivastigmine is a carbamate-type dual inhibitor of brain acetyl- and butyrylcholinesterases that has been evaluated in the symptomatic treatment of patients with mild to moderate dementia associated with idiopathic Parkinson's disease. Oral rivastigmine 3-12 mg/day for 24 weeks was significantly more effective than placebo in ameliorating cognitive and functional decline, including attentional deficits, in patients with Parkinson's disease dementia in a randomised, double-blind trial. The beneficial effects of rivastigmine observed in the double-blind trial were generally maintained in a 24-week extension of this study in which all patients received active treatment; placebo recipients who switched to rivastigmine also experienced improvements in their cognitive and functional symptoms at week 48. Rivastigmine appeared to be generally well tolerated, with the most common adverse events being mild to moderate in intensity and cholinergic in nature. Parkinsonian symptoms (mainly tremor) were more common in rivastigmine than placebo recipients.