Causes of Hallucinations & Delusions in Dementia and Caregiver Tips for Coping

Last Updated: May 27, 2022


 Imagine seeing a bug that isn’t actually there, and even feeling it crawl across the top of your foot. What if you were afraid that every time you couldn’t find something it was stolen, or believed any glass of water handed to you might be poisoned?

As dementia advances in the minds of our loved ones, their perceptions warp. Because hallucinations and delusions are symptoms of Alzheimer’s disease and dementia, it is vital for caregivers to understand what they are and how to cope.


What are Hallucinations?

With certain types of dementia, such as Parkinson’s disease dementia and Lewy body dementia, hallucinations are more common. Hallucinations are also seen in Alzheimer’s disease, but what exactly is the individual experiencing when they hallucinate? Hallucinations are the senses being wrong about what’s real. They are most often sights and sounds that do not exist outside the hallucinating person’s perception. Other senses can also be tricked by hallucinations like feeling something touching one’s skin when nothing is actually there. Typical hallucinations include hearing voices, seeing flashing lights, or watching bugs crawling on the floor.


Hallucinations are false feelings; delusions are false beliefs. For example, a person with dementia might believe that workers in a nursing home are poisoning meals or stealing. Delusions can be frustrating and difficult to deal with because they affect how someone with dementia relates to others. (Remember not to take offense because the behavior is caused by the disease.)

More generally, delusions take the form of paranoia. It can give the patient a sense that people are lying, acting in bad faith, or conspiring against them. Paranoia can come without any logical reasoning, and worsens as someone’s memory deteriorates.

What is Capgras Syndrome

About 15 percent of people with Alzheimer’s disease will experience Capgras syndrome, which is a specific type of delusional misidentification syndrome (DMS) that causes someone to believe that a friend or loved one has been replaced by an identical imposter. Capgras syndrome is most common in Lewy body dementia (see Which Dementias Cause Hallucinations? below). People with a history of anxiety are particularly vulnerable to Capgras syndrome if they have dementia. These delusions can be so strong that they’ll lead to violence, particularly from men. It is advised that the caregivers of people who have Capgras take precautionary steps like announcing themselves before entering a room because the syndrome seems triggered primarily by seeing a person’s face.


Causes of Hallucinations and Delusions

Hallucinations and delusions can be the result of the changes that dementia causes in the brain, but there are several other potential causes. Too much stimulation in the environment (noise, people, and other distractions), unfamiliar places and people, a variation in routine, and interactions between medications can all contribute to hallucinations and delusions.

Delusions are frequently the result of suspicion or paranoia on the part of the individual with dementia. Memory loss and confusion from the progression of dementia play into it. Science suggests that lack of information in the brain causes it to over-correct and make up new information. For instance, if someone with dementia forgot where he put down his glasses, because of poor memory and lack of awareness, he may decide someone stole them.

Hallucinations are sometimes present in a phenomenon called sundowning, which is characterized by increased anxiety in someone with dementia that hits late in the day, typically around sunset. Poor lighting and bad eyesight can cause shadows, and an individual with dementia might get startled by something that wasn’t really there.


Which Dementias Cause Hallucinations?

Hallucinations are most common for people with Lewy body dementia, an illness caused by the buildup of proteins called Lewy bodies that disrupt communication between brain cells throughout the brain (not just in one location like other dementias) or kill the cells altogether. Visual hallucinations will often occur in the early stages of the disease, though they eventually stop somewhere in the middle stages and won’t recur. People with Lewy body dementia often fluctuate between good days, when they’re thinking normally or at least fairly well, and bad days. In the early stages, those bad days are likely to include visual hallucinations.

Hallucinations will also occur for people with Parkinson’s disease with dementia, and for people with Alzheimer’s. Both those diseases are also associated with a buildup of proteins in the brain. With these dementias, though, hallucinations are more likely to be associated with hearing or feeling. Someone might have conversations with an imaginary person, for example, or think they’re being touched by something that isn’t there.


In What Stage of Dementia are Hallucinations and Delusions Most Likely to Occur?

The type of dementia most associated with hallucinations is Lewy body dementia. This affects about 1.4 million people in the U.S. and is the third-most-common type of dementia (following Alzheimer’s disease and vascular dementia). People with Lewy body dementia will often see colorful people or animals that aren’t actually present, often for a few minutes at a time. This is more likely to occur in the early stages of the disease than later. People with Lewy body dementia often have hallucinations early and then, as they enter the middle stages, the hallucinations will go away completely as other symptoms, like problems walking, get worse.

People with Alzheimer’s disease have been shown to sometimes have hallucinations, as with patients of Parkinson’s disease with dementia. This is rarer, however, and delusions (or paranoid misconceptions) are much more common with these illnesses. Both hallucinations and delusions in people with Alzheimer’s often occur in the late-middle to later stages of the disease.


Tips for Caregivers on Dealing with Hallucinations & Delusions

 Remember the 3 R’s: Reassure, Respond, and Refocus.

Consult a physician if your loved one is having delusions or hallucinations, to rule out other causes unrelated to dementia. Mental illness and medical conditions such as migraines, brain tumors, epilepsy, urinary tract infections, and dehydration can all be causes.

Resist the need to stop or control difficult behaviors. Think carefully about whether or not your loved one is causing a problem. If the answer is no, try letting it be. This is not to say that you have to lie to or “humor” your loved one; you can be honest while also showing respect. For example, you might say, ”I don’t hear or see anyone outside the window, but I know you do, and you seem worried.”

Consider the situation. Investigate why a hallucination or delusion is occurring in that particular moment. Beyond mental and medical causes, there can also be environmental and social causes as well.

Keep a journal to record when, where, and how your loved one experiences delusions or hallucinations. Record how your loved one is behaving, and what sorts of events have happened recently.

Control the environment. Make sure there is sufficient lighting in the room and not too many distractions. A radio or TV, for example, might cause your loved one to hear voices and not understand that what’s coming from the speakers is not actually in the room. Also, pulling curtains or shades can provide comfort for someone afraid of being watched.

Have backups. If there’s something like a favorite mug or glasses that your loved one keeps misplacing, have multiples of that same item. That way, frustration and the need to search won’t boil over into aggression.

Be flexible. Sometimes the kindest thing you can do is to tell a small fib. “It was just me that made that noise. I dropped a pan. Do you feel safe now?”

Employ the art of distraction. Creating an activity for your loved one to focus on can help to move past a hallucination. Music can help (for more information, click here), or getting out a photo album.

Demonstrate caring. Hallucinations and delusions are frightening, so address the feelings behind the behavior. Offer reassurance and show your loved one that you care. For instance, you might ask, “Would you like for me to stay here with you for a while?” or “Do you think a night light would look nice in this room?”


Treatment of Hallucinations & Delusions

Consulting with your doctor is vital to understand why your loved one is hallucinating or having delusions, and whether medication is necessary. For both delusions and hallucinations, medications called antipsychotics are sometimes prescribed. Antipsychotics, also called “neuroleptics,” are prescribed for health conditions including schizophrenia, and have been shown to help people with dementia who struggle with these symptoms.

Doctors may prescribe any of a number of antipsychotics after evaluating your loved one. The most commonly used to help dementia-related hallucinations and delusions is Risperidone. It has only been shown to alleviate symptoms in the short term. The side effects of Risperidone (and other antipsychotics can be severe) are muscle tremors, weight gain, fatigue, and dizziness. Because of this, non-drug treatments (suggested above) are typically preferred. A doctor may, however, conclude that medication is necessary.

Another non-pharmaceutical option is cannabidiol (CBD). Studies of the brain have shown that CBD’s effects can include alleviating hallucinations, delusions, and other behaviors associated with psychosis. All these benefits come without the harsh side effects associated with antipsychotics. CBD is extracted from the cannabis (marijuana) plant, but excludes the THC that produces the “high” effect from marijuana. It can be taken any number of ways besides smoking including ingesting it or using it topically. CBD is readily available throughout the United States because it is legal in all 50 states. For more information about CBD’s benefits for loved ones with Alzheimer’s or a related dementia, and whether it’s available in your state, click here.


Medications Under Consideration for FDA Approval for Hallucinations

To date, there is no medication that has FDA approval to help against hallucinations and delusions in Alzheimer’s patients. In the last year, Pimavanserin (or sold as Nuplazid) completed Phase 3 clinical trials and applied for FDA approval. Nuplazid is already FDA approved for Parkinson’s disease to help with symptoms of hallucinations and delusions. Nuplazid is different from what is currently available by the way it functions and its side effects. This medication targets a specific serotonin receptor in the brain that causes a chemical reaction and reduces delusions and hallucinations. Additionally, scientists are also proving that by affecting serotonin receptor 5-HT2A, amyloid-beta levels decrease. Amyloid-beta proteins form clumps in the brain of Alzheimer’s patients causing brain cells to die.

How is this different from what is currently prescribed? The largest difference from antipsychotics are lesser serious side effects. Traditional antipsychotics can have harmful effects that outweigh their benefits. A few include dizziness, worsening mobility, shakiness, sedation, confusion and an increased frequency to fall. Also, doctors say that continuous use of antipsychotics can lead to faster cognitive decline. That means it could accelerate the progression of the disease in some patients. Pimavanserin has a 65% rate of less hallucinations and delusions proving this medication has a greater medical benefit than risk. In comparison, side effects for Pimavanserin were constipation, headache, urinary tract infection or irregular heart rhythm (only in patients with heart problems).

When will Pimavanserin be on the market? It is estimated as early as August 2022 Pimavanserin could be FDA approved for hallucination and delusions in Alzheimer’s patients. This is dependent on its clinical trials proving its effectiveness. It was denied approval for Alzheimer’s use in 2021 because the FDA said the clinical trials didn’t back up the claim of its medical benefit. The company resubmitted the drug application and its clinical trials and the FDA agreed to review all the data again and make a new decision in the beginning of August.