Delusions and Hallucinations


  • Delusions and hallucinations are classified as psychoses.
  • Disruptions in thought and/or perceptions make it difficult to determine what is real and what is not.
  • They may be described as breaks with reality.
  • Psychoses occur with dementia, Parkinson’s disease, delirium, and other thought disorders.
  • Delirium is a sudden onset of worsening confusion, delusions, or hallucinations often associated with medications, infections, or hospitalizations.


  • Overactivity in the frontal lobe of the brain from too much dopamine leads to the misperceptions and breaks in reality.
  • Although delusions and hallucinations can occur with any dementia, they are more common in Lewy body dementia.


  • A hallucination is a perception that occurs without a known connection to reality.
  • It can be as simple as seeing dots on a wall or as complex as seeing groups of people.
  • Any of the five senses can be involved in a hallucination.
    • Tactile – Feeling bugs crawling on the skin
    • Taste – Having a bad taste in the mouth
    • Smell – Sensing a bad smell
    • Sight – Seeing things that are not there, commonly animals or people
    • Hearing – Hearing sounds that are not perceived by others.


  • They are fixed, false, or idiosyncratic beliefs.
    • Fixed – It is the reality for the person, and they cannot be talked out of it.
    • False – It is incorrect.
    • Idiosyncratic – It is not believed by other people.
  • They are distinct from confabulation, remembering a portion of a memory, and filling in the gaps with misinformation.
  • Types of delusions
    • Paranoid – Belief that someone intends to do harm, such as poisoning food or stealing items
    • Jealousy – Belief that the spouse is having an affair
    • Misidentification – Belief that someone they know is really an imposter
    • Somatic – Belief that something is physically wrong
    • Mirrored self-identification – Belief that the person in the mirror is an intruder
    • Grandiose – Belief that they’re superior to others or indestructible


Behavior modification 

  • Reassure the person if they are upset or agitated, making statements like “you are safe” or “I am here.”
  • Avoid trying to correct the delusion and presenting information to disprove it. It is a fixed idea.
  • Keep statements clear and concise.
  • Use a portion of the delusion to change the direction of the conversation. For example, if the person says their mom is coming to dinner, but she is actually deceased, talk about the mom and a happy memory associated with her.
  • If the delusion is triggered by the presence of an individual, have that person leave from the area if it is safe to do so.
  • Use distraction by changing the person’s attention to a task or activity.
  • Calming activities such as aromatherapy, light massage, pet therapy, or music may help.


  • Medications are used if the delusion or hallucination is causing the person emotional distress or if safety is threatened, such as the desire to leave the home or the person is physically aggressive.
  • Antipsychotic Medications
    • Examples are quetiapine (Seroquel) and risperidone (Risperdal)
    • Serious side effects may occur.
      • BLACK BOX warning – There is an increase in the mortality rate in patients with dementia who are given antipsychotics.
      • Movement symptoms can worsen when used by people who have Parkinson’s disease or Lewy body dementia, increasing the risk of falls.
      • A potentially fatal heart rhythm may occur with use; therefore, close monitoring is necessary.
  • Additional medications may be used.
    • Antidepressants to treat underlying anxiety or depression which may be the trigger for the psychotic behavior.
    • Mood stabilizers and sedatives may be used to treat patients with severe agitation from psychosis.