There's a chance that an antipsychotic medicine you take is making your Parkinson's worse. If that happens, you have alternatives. The medication pimavanserin (Nuplazid) was approved by the FDA to specifically treat psychosis that goes along with Parkinson's disease. Other drugs, such as olanzapine (Zyprexa), quetiapine (Seroquel), and clozapine (Clorazil) can control hallucinations at low doses without making your Parkinson's symptoms worse.