Experiencing a hallucination means perceiving something that is not really there, for example, through vision, hearing, or touch. It is important to understand their role in Parkinson's disease — among people with PD who take medication to improve their mobility, about 20 to 30 percent experience visual hallucinations.

First, people with PD should understand that hallucinations are most often a side effect of medication. They are part of the treatment of PD and not necessarily a sign that someone’s cognitive abilities are declining. It is also important to note that most people with PD most commonly experience visual hallucinations that are fleeting and non-threatening. However, in some cases the hallucinations may affect other senses or become threatening or bothersome. Whether to treat hallucinations depends on how much they bother a person with Parkinson’s.


  • Among the types of hallucinations, visual are the most common type experienced by people with PD. They tend to appear in the evening or at night, when visibility is reduced and there are shadows.
  • Although hallucinations can affect anyone taking PD medications, they are more common in people with some problems in thinking or memory or when the person is undergoing a medical stress such as after surgery or during a bladder infection or pneumonia.
  • Very often the visual hallucination is really an illusion or misperception. The clothes in the closet may look like a group of people or the shrubbery outside may look like an animal.
  • A person with PD may experience a hallucination in the peripheral vision (out of the corner of the eye), in which he or she see flashes of light, small animals such as cats or dogs or people. Often the image will disappear when the person looks more closely.
  • Sometimes people with PD have “presence hallucinations” — the feeling that someone is in the room with them or standing behind them. Some people with PD experience hallucinations that involve senses other than vision. These include sounds or voices, or physical sensations.
  • Most often these illusions and hallucinations are not frightening and the person is aware that they are a trick of the mind. However, some people find them very real.
  • In some cases, people with PD have hallucinations that are threatening or frightening, or part of a delusion. A delusion is a persistent thought that has no basis in reality; commonly that a spouse is unfaithful or that someone is trying to hurt the person.


It is extremely important to tell your family and doctor if you are experiencing hallucinations. Talking to your doctor can help reassure you that it is the treatments that are most to blame and that medication adjustments are very likely to help. The doctor will review your health status and medications and come up with a treatment plan if needed. Keep in mind that:

  • Treatment for hallucinations depends on how much they bother a person, or interfere with life.
  • Having hallucinations does not necessarily mean that a person’s PD medications need to be changed.
  • If a change in medication is in order, the first step usually is to eliminate medications that are no longer needed, and then to reduce medication for PD movement symptoms.
  • If it is not possible to take a lower dose of PD medications, your doctor may prescribe a low dose of a cholinesterase inhibitor like donepezil (Aricept®), rivastigmine (Exelon®) or galantamine (Razadyne®) or a low dose of an antipsychotic drug. However, these drugs — which include quetiapine (Seroquel®), and clozapine (Clozaril®) must be used with caution as they can have side effects.

Tips for Living With Hallucinations

If you have hallucinations, be aware that they are usually a side effect of medication and not necessarily a sign that cognitive abilities are declining. Your doctor will monitor the hallucinations and your cognitive function carefully to decide whether intervention is required.

  • Good lighting and stimulating activities in the evening can help keep some hallucinations at bay.
  • Care partners can help to reassure a loved one with PD -- both by validating their partner’s experience (hallucinations seem very real for them) but also reassuring them that they will be safe from any frightening ones.
  • Know that different approaches to the emotional management of hallucinations -- for yourself, a loved one or patient -- may work on different days or at different times of day.
  • It is important that people with PD talk about hallucinations with their family and with their doctors because they are manageable and can be troublesome if not properly treated.

Do you have additional questions? Click here to watch our video featuring people who live with PD speak about how hallucinations impact their lives, and to find facts from movement disorders specialist led by Joseph H. Friedman, M.D., of Brown University. Also be sure to see our announcement here from spring 2016, detailing a drug newly-approved to treat hallucinations associated with Parkinson's psychosis.