You probably already know that the non-motor symptoms of Parkinson's disease are often more difficult to manage than the motor problems. It happens that about 20 percent of people with Parkinson's disease suffer from Parkinson's psychosis during the course of the disease. This is commonly associated with mental illnesses such as schizophrenia, but is also a common complication of other diseases, including Parkinson's.

Psychoses usually only appear in the later course of Parkinson's disease. Almost three quarters of people who have lived with Parkinson's for 20 years or more will develop psychosis over time. This usually takes the form of hallucinations or delusions.

Hallucinations are delusions of perceiving something that is not actually there. They can be connected to the senses and manifest as something seen, heard, tasted, touched or smelled. Hallucinations in Parkinson's disease are usually visual, that is, seeing people or things that are not visible to others. Although these hallucinations appear real to those affected, they remain invisible to others. There are also insight hallucinations, where the person with Parkinson's understands that what is being experienced is not real.

In the early stages of Parkinson's psychosis, it is important to discuss your hallucinations with your doctor, family or nurse. Open communication can lead to a quick diagnosis and, if necessary, to targeted treatment. This way you can be helped to deal with this new disorder.

In the further course of Parkinson's psychosis, however, the ability to see can be lost. When this happens, caregivers may see you becoming increasingly confused and restless. Some people also try to interact with their hallucinatory images. Loss of insight can be dangerous for you as a person with Parkinson's disease and for those around you. It requires special patience and attention from the caregivers.

Delusions are fixed, false beliefs that seem real to you, the patient. They cannot be controlled and fall into different categories such as jealousy, paranoia and somatic delusions. The most common form of delusion in Parkinson's is paranoia, where you may suspect spousal infidelity, for example, or fear your food or medication will be poisoned. Delusions occur in about 10 percent of people with Parkinson's. Therefore, it is important to report all possible examples to your doctor.

Parkinson's disease is a neurodegenerative brain disease that affects the production of substances important for controlling movement and balance. The drugs used to relieve motor symptoms increase dopamine levels. However, too much dopamine can cause hallucinations and delusions. Other features of disease progression, such as cognitive and visual perceptual changes, may also contribute to these psychological changes.

It is important that your family and caregivers are aware of the risk factors and share them with the doctor. Even reversible causes such as urinary tract infections, sleep disorders and medication changes can be the cause and treated. Even over-the-counter medications and Dietary Supplement can pose risks for people with Parkinson's.

Adjusting the medication with antiparkinson drugs is a challenging task in order to get both the motor problems and the psychological symptoms under control. The medical team can substitute specific medications or adjust the dosage to find the best solution for you. Older people and people with vision problems are also at higher risk of developing this type of psychosis.

Treatment options depend on the cause of the hallucinations and delusions. Your medical team will assess your condition in three general steps: taking a complete medical history, assessing the stage of your Parkinson's disease, and assessing the impact of the psychological symptoms. Your medication will then be adjusted to find the right balance. In some cases, the use of antipsychotics may be necessary. In 2016, the drug pimavanserin was approved specifically for the treatment of Parkinson's psychosis, which does not impair motor performance.

Caring for people suffering from hallucinations or delusions can be frustrating and scary. Having a caregiver's support is just as important as treating and managing a loved one's condition.

If you have additional questions or need assistance, do not hesitate to contact your medical team. They are at your side to give you the best possible support.

Jürgen Zender in July 2023