A hallucination involves seeing, hearing, or sensing something that is not there. A delusion is a firmly held false belief.
These experiences can occur with Alzheimer's and other dementias. They are different from ordinary forgetfulness.
Sources: Alzheimer's Association on hallucinations and delusions
A person may describe someone in the room whom others cannot see. Another person may believe someone has stolen an item that has been misplaced.
You do not need to choose the correct medical label before asking for help. Describe what the person said, how they reacted, and whether the experience seemed frightening.
Other health problems, medicines, and changes in vision or hearing can contribute to hallucinations. A medical evaluation can help identify possible causes. Do not assume a new symptom is simply part of Alzheimer's. Source: Alzheimer's Association
Contact the care team promptly about new symptoms, especially sudden changes or concerns about safety.
Stay calm and acknowledge distress without arguing about the experience. You might say: “You seem frightened. I am here with you.”
Ask the care team for strategies that fit the person's situation. Treatment decisions require individual evaluation.
Source: Alzheimer's Association
Record the person's own words, when the event happened, and any recent health or medicine changes.
Also tell the clinician how it is affecting both the person and the caregiver. Sleep disruption, fear, and difficulty managing safely at home are important parts of the discussion.
Understanding the terms can help, but you do not have to handle these changes alone.