Dementia Hallucinations: What They Are and How to Respond

Dementia hallucinations are experiences of seeing, hearing, smelling, tasting or feeling something that is not there, caused by changes in the brain. They are most common in dementia with Lewy bodies and Parkinson's disease dementia, and usually come later in Alzheimer's disease.

A new or sudden hallucination needs a doctor first, because infection, delirium, medicines and poor eyesight or hearing can all cause them. In the moment, stay calm, do not argue, reassure your parent and look for what in the room may have set it off.

We read the pages that rank for this search (the Alzheimer's Society, Healthline, UCLA Health, NCCDP and the Alzheimer's Association), then checked every fact against official and academic sources: the Alzheimer's Association, the Alzheimer's Society, the Lewy Body Dementia Association, the NHS and a 2022 study in Drugs and Aging. We read them on November 13, 2026. This guide is general information, not medical advice.

Families often use one word for three different things. Telling them apart helps you respond, and helps the doctor.

Hallucination. Your parent senses something that is not there at all. Example: seeing a man standing in the corner of an empty room, or hearing someone talk when the house is quiet. The NHS says hallucinations appear to be real but only exist in the mind.

Delusion. Your parent firmly believes something that is not true. Example: that a purse was stolen, that food is poisoned, or that a spouse is an impostor. The Alzheimer's Society calls delusions strongly held false beliefs and says they are common in dementia.

Misperception. Your parent mistakes something real for something else. Example: a patterned carpet seen as insects, or a coat on a hook seen as a person. The Alzheimer's Society says many people described as hallucinating are in fact misperceiving.

They can overlap. The Lewy Body Dementia Association says delusions and paranoia sometimes follow frightening hallucinations, and the Alzheimer's Society notes that a person who cannot find something may believe it was stolen and start hiding things.

Dementia with Lewy bodies. The Alzheimer's Association lists recurrent, well-formed visual hallucinations as a core symptom, and says hallucinations and misidentifying familiar people are much more frequent in early dementia with Lewy bodies than in Alzheimer's. The Lewy Body Dementia Association says visual hallucinations occur in up to 80% of people with Lewy body dementia. The Alzheimer's Society describes them as often vivid and realistic, lasting several minutes.

Parkinson's disease dementia. The Alzheimer's Society says hallucinations are also common here. A 2022 study in Drugs and Aging, citing earlier research, says hallucinations affect over half of patients with Parkinson's disease dementia and dementia with Lewy bodies.

Alzheimer's disease. The same study says hallucinations affect one in five patients with Alzheimer's disease. The Alzheimer's Association says they usually happen in the later stages. Among the older Americans with dementia followed in that study, 41.4% reported hallucinations at least once.

Other types. The Alzheimer's Society says other types of dementia may also cause hallucinations, and that delusions are less common in frontotemporal dementia.

Seeing people or animals. The Alzheimer's Society says visual hallucinations are the most common type in dementia and can be complex, such as people, animals or strange scenes. The Alzheimer's Association gives the example of seeing a former friend's face in a curtain.

Insects or things on the skin. Seeing insects on a hand, or feeling them on the skin, appears in both Alzheimer's Association and Alzheimer's Society guidance.

Hearing voices or footsteps. Your parent may hold a conversation with someone who is not there. Check hearing first: the Alzheimer's Society says auditory hallucinations may be linked to hearing problems or hearing aid settings.

A stranger in the mirror. A parent who no longer recognizes their own reflection may think someone else is in the house. The Alzheimer's Association suggests covering or removing mirrors when this happens.

Smells and tastes. Smoke or perfume that no one else smells, or a metallic taste. The Alzheimer's Society says taste changes can come from tooth decay or denture cream, so a dental check helps.

Some are pleasant. The Alzheimer's Association says some hallucinations are ordinary images of people or objects from the past. Not every hallucination is frightening.

No source we read gives one single cause, but several things meet in the evening. Low light makes shadows and reflections easier to misread. UCLA Health's caregiver video shows a mother waking at night frightened by a shadow cast by a coat rack and hat; the answer was to remove them. The NHS lists waking up or falling asleep, sleep deprivation and hunger among temporary causes of hallucinations.

In Lewy body dementia, sleep itself can be disturbed. The Alzheimer's Association lists REM sleep behavior disorder, acting out dreams, as a core symptom, and the NHS mentions disturbed sleep with violent movements and shouting out. Tell the doctor if your parent seems to be acting out dreams, because that is a different problem from a waking hallucination.

If the confusion builds every late afternoon, our guide sundowning-dementia-home-management covers that pattern, and dementia-sleep-changes-and-solutions covers night waking.

Never assume a new hallucination is just the dementia. The Alzheimer's Association says anyone who starts hallucinating should have a medical evaluation to rule out other causes. Sources list these:

Infection and delirium. The Alzheimer's Association names kidney and bladder infections. The Alzheimer's Society says infections such as pneumonia can cause delirium, that some people with delirium hallucinate, and that delirium is a medical emergency.

Medicines. Hallucinations are a rare side effect of many drugs, and the Alzheimer's Society says Parkinson's medicines often trigger them. New or combined medicines can cause them. Do not stop or change any medicine without the doctor.

Eyesight and hearing. Both organizations recommend eye and hearing checks.

Dehydration, pain, constipation, hunger or thirst. The Alzheimer's Association names dehydration and intense pain, and the Alzheimer's Society suggests checking for hunger, thirst, discomfort and constipation.

Other illness. The Alzheimer's Society lists fever, seizure, stroke and migraine.

Get urgent help the same day if hallucinations involve more than one sense, frighten your parent, last a long time, happen often, or come with more confusion than usual, which is the Alzheimer's Society's list. The NHS says to get emergency help, which in the US means calling 911, if someone is very agitated or aggressive, wants to harm themselves or others or hears voices telling them to, has hallucinations that are quickly getting worse, suddenly becomes confused, or is not making sense when speaking.

1. Ask whether it is a problem. The Alzheimer's Association suggests first deciding whether the hallucination is upsetting your parent or leading to danger. If your parent is calmly chatting to a visitor no one else can see, you may not need to do anything. The Lewy Body Dementia Association says that when hallucinations do not frighten the person, drug treatment may not be needed even if the family finds them bothersome.

2. Do not argue. The experience is real to your parent. Every source we read says arguing raises distress. UCLA Health warns against turning on the light to prove nothing is there and sending them back to bed.

3. Be honest without denying. The Alzheimer's Association suggests acknowledging what your parent sees while saying you do not see it yourself. Try: "I don't see him, but I can tell you're worried. I'm here."

4. Reassure and comfort. The Alzheimer's Association suggests words such as "Don't worry. I'm here. I'll protect you," and a gentle touch. Respond to the feeling, fear or loneliness, rather than the content.

5. Check the room. Look for a shadow, a reflection, a TV, a patterned surface or a noise that could be misread. The Alzheimer's Association names TV and air conditioner sounds.

6. Move and distract. Suggest a walk or another room. The Alzheimer's Association says frightening hallucinations often ease in well-lit areas with other people present. Music, conversation or a small task can redirect attention.

7. Note it down afterward, while you remember the details. More on what to record below. For words that help in hard moments, see dementia-communication-tips-that-help.

A calm hallucination that your parent enjoys or ignores usually needs patience and a note in your log, not action. Watch for changes: more frequent episodes, new senses involved, fear, accusations, refusing food or medicine because of what they see, or trying to escape or defend themselves. Those need a call to the doctor.

If fear turns into hitting, shouting or pushing away care, our guide dementia-agitation-aggression-guide explains how to calm things without escalating. Keep yourself safe first.

Light. Keep rooms evenly lit in the evening and use night lights on the way to the bathroom. The Alzheimer's Association recommends adjusting lighting to reduce shadows, reflections and distortions on floors, walls and furniture.

Mirrors and windows. Cover or remove mirrors if your parent sees a stranger, and close curtains at dusk so dark glass does not reflect the room.

Clutter and shapes. Remove coats on hooks, piles of clothes on chairs or anything that looks like a figure in poor light. Plain surfaces are easier to read than busy patterns.

Sound and screens. The Alzheimer's Association suggests listening for sounds that could be misread, such as the TV or the air conditioner. Turn off upsetting programs and lower background noise.

Senses. Book eye and hearing tests, keep glasses clean and hearing aid batteries fresh, and check the hearing aid settings.

Routine. Keep meals, drinks and bedtime at regular times. Keep things in the same places, which the Alzheimer's Society also suggests for delusions about theft.

Bring notes. The Alzheimer's Society suggests recording what your parent saw or sensed and the words they used, the time of day and anything just before it such as a nap or a meal, where it happened, how long it lasted and how your parent reacted. Bring a full list of medicines and doses, including over-the-counter products, and any alcohol use.

Treatment decisions belong to the doctor. The Alzheimer's Association says non-drug approaches are the first line of treatment for behavioral symptoms, and medicines may be considered if those fail and symptoms are severe. The Alzheimer's Society says hallucinations, particularly in dementia with Lewy bodies, may respond to anti-dementia drugs.

If your parent has, or may have, Lewy body dementia, tell every doctor, including in the emergency room. The Alzheimer's Association says antipsychotic drugs should be used with extreme caution in Lewy body dementia and may cause serious side effects in as many as 50% of people with it, including sudden changes in consciousness, impaired swallowing and acute confusion. The Alzheimer's Society says people with dementia with Lewy bodies are at particular risk of severe harmful reactions to antipsychotics, and that in dementia generally these drugs increase the risk of stroke and death. Ask the doctor about risks and benefits before any new prescription.

Charles Bonnet syndrome causes visual hallucinations in people who have lost a lot of their sight, for example from macular degeneration or cataracts. The NHS, in guidance reviewed June 17, 2026, says it is not caused by a mental health problem or dementia, that the hallucinations are visual only, and that most people know they are not real. Images can be patterns, people, animals or places, lasting minutes or hours.

A parent with dementia and poor eyesight could have either, or both. The NHS still advises getting hallucinations checked to rule out more serious causes. Mention any recent change in sight to the doctor and book an eye exam.

Hallucinations can frighten the whole household, and night episodes cost everyone sleep. Tell the doctor how you are coping too, not only how your parent is.

The Alzheimer's Association Helpline, 800.272.3900, and its ALZConnected online community are free. Ask a relative or friend to cover one evening a week so you can sleep.

If nights are wearing you down, Dementia In Home sends 3 video profiles of caregivers with dementia experience within 48 hours, free. This is non-medical help at home. Call (689) 333-6079.