Parkinson’s Disease Psychosis
Parkinson's Disease Psychosis: A Patient and Caregiver Guide
As a patient with Parkinson’s disease or a caregiver of a patient with Parkinson’s disease, you may already be familiar with many of the motor and nonmotor symptoms of Parkinson’s. However, there are other less obvious effects of the disease on the brain, as Parkinson’s disease is a neurodegenerative disorder. In addition to the tremors, stiffness, slow movement, and muscle cramping, Parkinson’s disease may cause severe confusion (disordered thinking), seeing things that are not actually present (hallucinations), and believing things that are not true (delusions). Together, these features are referred to as psychosis, or Parkinson’s disease psychosis, as these changes reflect a change in perception of reality that result from this neurodegenerative process.1,2
Parkinson’s disease psychosis is a medical condition that results in a loss of contact with reality, and is different from the ordinary definition of psychosis that occurs in psychiatric disorders. Parkinson’s disease psychosis is different; it is not a result of a psychiatric disorder and is generally not associated with psychotic symptoms. Parkinson’s disease psychosis may manifest as hallucinations, illusions, or delusions and is managed by a neurologist using medications that help reduce symptoms with minimal effects on motor symptoms.1,2
A type of medication called an atypical antipsychotic has been studied in Parkinson’s disease psychosis. Although limited data exist on the efficacy of these agents such as clozapine, stringent monitoring requirements are in place for clozapine, specifically related to the levels of immune cells in the blood called neutrophils. Another medication that has been evaluated for safety but has limited evidence for efficacy in Parkinson’s disease psychosis is the atypical antipsychotic quetiapine. Atypical antipsychotics may also affect motor performance. A different medication specifically designed for Parkinson’s disease psychosis known as pimavanserin works on a specific pathway in the brain, the serotonin system, to target a specific receptor that has been associated with hallucinations, delusions, and illusions. Because pimavanserin acts on a specific pathway in the brain, unlike atypical antipsychotics, it does not affect motor performance in people with Parkinson’s disease.1,3-6
When talking with your physician about Parkinson’s disease psychosis, it can be difficult because any type of disease of the brain can lead to feelings of loss of control and embarrassment. It is important to recognize that your physician knows this condition is caused by a process in the brain and options exist for managing this condition. Discussing symptoms openly and various treatment options that can improve symptoms is the first step in managing this important aspect of Parkinson’s disease. Sharing information about your symptoms can help caregivers and physicians better assess and address Parkinson’s disease psychosis.1
Beyond medication, caregivers can take many steps to improving symptoms for patients with Parkinson’s disease psychosis. Caregivers can help patients discuss their symptoms with physicians. Caregivers can also help maintain a sense of calm and patience when patients are experiencing symptoms. Increasing lighting levels, especially at night, can help reduce hallucinations by reducing shadows, which can be interpreted in different ways by people with Parkinson’s disease psychosis. Although it may be helpful in all patients, patients with Parkinson’s disease psychosis symptoms who maintain insight should be reminded that what they are experiencing is not real. However, distracting or agreeing with patients who do not have such insight may be a more productive approach.1
- Parkinson’s Foundation. Psychosis: a mind guide to Parkinson’s disease. https://www. parkinson.org/pd-library/books/Psychosis-A-Mind-Guide-to-Parkinsons-Disease.
- Kalia LV, Lang AE. Parkinson’s disease. Lancet. 2015;386(9996):896-912. doi:10.1016/ S0140-6736(14)61393-3
- Hacksell U, Burstein ES, McFarland K, Mills RG, Williams H. On the discovery and development of pimavanserin: a novel drug candidate for Parkinson’s psychosis. Neurochem Res. 2014;39(10):2008-2017. doi:10.1007/s11064-014-1293-3
- Pimavanserin (Nuplazid®) PI 2020 (https://www.accessdata.fda.gov/drugsatfda_docs/ label/2020/207318s010lbl.pdf).
- Clozapine (Clozaril®) PI 2014 (https://www.accessdata.fda.gov/drugsatfda_docs/ label/2014/019758s073lbl.pdf).
- Quetiapine (Seroquel®) PI 2016 (https://www.accessdata.fda.gov/drugsatfda_docs/ label/2016/020639s064lbl.pdf).