Explaining the “Psychosis Spectrum” in Parkinson’s Disease

Hallucinations and delusions can begin in the later stages of PD. Experts describe how these symptoms can progress—and how best to treat them. Many people with Parkinson’s disease (PD) develop psychosis, a condition where they see or believe things that aren't real. This usually occurs in the later stages of PD and can include mild hallucinations, like seeing shadows, which can progress to more vivid and troubling visions or delusions. About 20% to 40% of PD patients experience psychosis, although some studies suggest it could be as high as 70%. Early signs are often mild and recognized as unreal, but as the disease progresses, patients might lose this awareness, leading to more severe and distressing symptoms, like believing a loved one is an intruder or seeing frightening things that aren't there. Psychosis in PD is mainly due to brain deterioration affecting sensory and attention-processing areas. It can also be triggered by PD medications and other health issues like infections or dehydration. Managing PD psychosis involves adjusting medications and possibly using specific drugs like Nuplazid (pimavanserin), which is FDA-approved for PD psychosis, or Seroquel (quetiapine), which can help but may have side effects. Discussing symptoms with a doctor is crucial for timely and effective treatment.