- Use of any of the following in the 3 weeks prior to the screening visit: (a) a neuroleptic or atypical antipsychotic medication; or (b) an anticholinergic drug, amantadine for the treatment of parkinsonism [treatment with levodopa (Sinemet, Sinemet CR) and any dopamine agonist, selegiline or entacapone is allowed].