Understanding Parkinson’s disease psychosis

“A stranger was in my room last night.” “This cereal has beetles in it.” “My nurse has a butcher knife!”  None of these are true, but to a resident with Parkinson’s disease psychosis, they are very real indeed.

About 70 percent of long-term care residents who have Parkinson’s disease will develop the psychosis, a condition that includes visual and sometimes graphic hallucinations. 

Unlike schizophrenia, which tends to be much more auditory, most Parkinson’s psychosis events are visual, explains Jason Kellogg, MD, Chief of staff at Newport Bay Hospital, an acute psychiatric facility in Newport Beach, Calif., that provides geriatric psychiatry services. He also is the founder and owner of Progeny Psychiatry Group in Orange County.

“Reactions can be ‘I see someone standing at my bed’ or ‘Look at those ants on the wall!’ Or, it can be a more persecutory type, like ‘People are trying to poison me,’” Kellogg explains. “The delusions are something that the nurses are probably used to; it’s just that the hallucinations can be a little different.”

The daily contact with residents means caregivers are usually the first to notice symptoms of Parkinson’s psychosis. At first, many residents are able to discern between reality and the hallucinations, realizing that they are “seeing things” or having delusional thoughts, Kellogg says. Later on, their ability to recognize the hallucinations as false will fade, and the visions will seem as real to them as the walls.

For residents in later stages, correcting the resident has little value. Instead, caregivers may find reorientation or validation therapy more useful, he explains. “If the patient says there is a stranger standing in his room, you might say, ‘That must be very distressing; how can I help you?’ rather than saying, ‘There’s no one in your room.’”

Better staff training can go a long way. “Understanding a diagnosis helps us be more sensitive to it,” Kellogg says. “Having a better eye for it and understanding the differences between psychosis and dementia can help the staff contribute helpful information to doctors.”

Treatment of Parkinson's psychosis is a frustrating circle of side-effects. Parkinson’s psychosis has no cure, and to date, no medications have been approved by the Food and Drug Administration specifically to treat it. Anti-Parkinson's medications (particularly dopamine receptor agonists) are the most common cause of the psychosis, notes an article in Drugs & Aging journal.

Achieving the delicate balance of enough dopamine to control tremors but not enough to worsen psychosis means diligent medication management is key. Medication reviews also can help physicians determine whether the hallucinations are related to Parkinson's psychosis, adverse drug events, dementia or a combination. Changing medication dosage or prescribing different combinations takes time and patience, notes the National Parkinson Foundation, and caregivers can help families understand the importance of finding just the right drug combination.

Some providers use drugs designed to treat schizophrenia, but often find that the side-effects aren’t worth it, Kellogg says. “The medication is either grossly inadequate or toxic—sometimes actually worse than the Parkinson’s tremors. If I treat the psychosis, I make their motor [problems] seem worse, and if I don’t treat the psychosis, then the psychosis gets worse.”

Pamela Tabar

Pamela Tabar was editor-in-chief of I Advance Senior Care from 2013-2018. She has worked as a writer and editor for healthcare business media since 1998, including as News Editor of Healthcare Informatics. She has a master’s degree in journalism from Kent State University and a master’s degree in English from the University of York, England.