Hallucinations and Delusions
Updated: Apr 5
About 20-40% of people with Parkinson’s report that they experience hallucinations or delusions. This can happen from a side effect of PD medication, it can be a symptom of Parkinson’s, or a symptom of a different condition such as dementia. Want to learn more about dementia? Read our dementia article.
What are Hallucinations?
Hallucinations are tricks played by the brain. They involve your body’s senses, such as seeing, hearing, or feeling someone or something that is not really there. Hallucinations happen when you are awake, so don’t confuse hallucinations with dreams or nightmares. Sometimes people can be aware that hallucinations are happening in real time. This is called “retaining insight” but some people lose insight as the disease progresses.
There are a few different types of Hallucinations
Visual - Visual hallucinations are the most common type of hallucinations experienced in people with PD. They are more likely to happen when in an environment that is low light or low visibility. These hallucinations can occur in your peripheral vision, sometimes in the form of a flashing light, or people or small animals running by. When people try to look more closely, the images disappear.
Auditory - Auditory hallucinations are not as common and are only reported by a small percentage of people with PD. Examples of auditory hallucinations are hearing voices or sounds that are not real.
Olfactory - Olfactory hallucinations are very rare in PD, as people with PD can lose their sense of smell. This can be experienced by smelling an odor that is not related to an actual source.
Tactile - Tactile hallucinations are also very rare in PD. Tactile hallucinations are when sensations like bugs crawling on your skin are felt.
Gustatory - Gustatory hallucinations is another rare hallucination in PD. This is when you can sense a bitter or abnormal taste in your mouth.
What are Delusions?
Delusions affect about 8% of people with Parkinson’s Disease. Delusions are irrational, illogical, and dysfunctional thoughts that are not based on reality. They are not intentional thoughts but they are very real to the individual having them.
Delusions are less common in people with Parkinson’s compared to visual hallucinations. However, they are more complicated and can be a greater risk for behavioral disturbance and safety concerns. Delusions also tend to be more difficult to treat compared to hallucinations.
Delusions can start as general confusion at night, and progress to more clear delusions and behavioral disturbances during the day. People with delusion may become agitated and aggressive.
It is important to note that hallucinations are not necessarily a sign of cognitive decline. In fact, most hallucinations are fleeting and non-threading. Hallucinations or delusions can happen in infections such as a urinary tract infection (UTI) and can also occur during your “off” period, so it is important to talk with your neurologist if you are experiencing symptoms of hallucinations or delusions. Different medications can also contribute to hallucinations or delusions such as:
anticholinergics, such as trihexyphenidyl (Artane) and benztropine mesylate (Cogentin)
COMT inhibitors, such as entacapone (Comtan) and tolcapone (Tasmar)
dopamine agonists, including rotigotine (NeuPro), pramipexole (Mirapex), ropinirole (Requip), pergolide (Permax), and bromocriptine (Parlodel)
MAO-B inhibitors, such as selegiline (Eldepryl, Carbex) and rasagiline (Azilect)
narcotics containing codeine or morphine
NSAIDs, like ibuprofen (Motrin IB, Advil)
How can your loved ones help?
If you are living with a loved one or care giver and you have hallucinations or delusions, it is important to talk to them about how they can help you. Asking yourself the following questions can help determine what their roles can be when you are experiencing a hallucination or delusion.
What happens/what does it feel like when you experience hallucinations or delusions?
When or where do they most likely happen?
Is there something that makes them happen less often and less intensely?
How can your loved ones make things easier for you?
Your loved ones can also help track your symptoms, like tracking what you were doing before they started and what exactly you thought you experienced. They can also try to keep you calm and remove anything stressful from the environment to keep you from being panicked.
If you think you are experiencing hallucinations or delusions, talk with your neurologist!