Dementia steadily damages parts of the brain. For this reason, people with dementia may experience delusions and hallucinations. This can lead to symptoms of paranoia and cause mistrust of others.

Sudden paranoia, agitation, and similar symptoms can also signal an underlying health issue. For example, people with dementia can experience delirium, a state of confusion that can occur as a result of a medical condition.

It is difficult to estimate how common delusions and hallucinations are among people living with dementia. This is because a person cannot always tell others about their experiences, especially in the later stages. Research from 2020 estimates that 30% of people with dementia experience delusions and hallucinations, but the actual figure may be much higher.

Because dementia paranoia has many potential causes, caregivers should consult a doctor if their loved one experiences this symptom.

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Dementia damages a person’s brain. This affects their ability to think clearly, understand the world around them, and process their emotions. It may also cause changes in their perception of reality.

People with dementia may experience:

  • delusions, which are false beliefs that feel very real
  • hallucinations, which are instances of seeing or hearing things that are not real
  • paranoia, which is a feeling that other people are a threat

Delusions or hallucinations may lead to paranoia, or the paranoia may occur on its own as a general feeling. If a person does feel that they are in danger of some kind, they may make accusations, such as that:

  • people are stealing from them
  • a partner is cheating on them
  • people are out to get them

Any type of dementia can cause delusions and paranoia, but certain types may be more likely to cause it than others.

For example, people with frontotemporal dementia commonly experience behavior changes, lack of insight into their behavior, and similar symptoms that may result in paranoia.

Potential causes of dementia paranoia include:

  • brain damage from the disease itself, which may change how a person thinks
  • hallucinations, which may cause a person to think they have seen evidence that others are untrustworthy
  • memory problems, which may cause a person not to remember who they talked to, what they did, or where they put a treasured object
  • fear or anxiety, which may make a person feel that the world or people around them are dangerous
  • a change in environment or routine

Another potential cause of delusions and paranoia is delirium. This is a state of mental confusion that develops fairly suddenly as a result of an underlying medical problem. It can occur in people with or without dementia.

However, because delirium can also cause hallucinations or incorrect beliefs, it can be difficult to distinguish from dementia symptoms. If a person suddenly begins experiencing these symptoms or if their symptoms suddenly worsen, they may have delirium and dementia at the same time.

In people who cannot articulate their needs or feelings, delirium could be the only symptom of a health condition. It is important to consult a doctor if there is a chance that a person could have delirium.

Potential causes of delirium include:

The development of dementia itself may also raise the risk of delirium, although scientists are still learning about the relationship.

Paranoia, hallucinations, and delusions can occur at any stage of dementia. Dementia is an unpredictable disease, so there is no way to predict how any individual’s condition will progress. Additionally, not all people will experience the same symptoms.

Forms of dementia that affect mental health and behavior may cause paranoia earlier in the course of the disease. In other forms of dementia, such as Alzheimer’s disease, paranoia may occur later in the disease.

However, every person’s experience with dementia is different.

Dementia does not follow an orderly, predictable course. This means there is no way to predict how long episodes of paranoia will last or how long a person will display this symptom.

There are many types of dementia, and they manifest differently in each person. Some people may have occasional paranoia, while in others it may be a constant feature of the disease. It may worsen when a person is confused or if they are also experiencing delirium.

When a person has delirium that leads to paranoia, the paranoia may last as long as the delirium.

Research on the use of dementia medication for managing delusions has shown mixed results. Instead, doctors may prescribe antipsychotic medication to address delusions and paranoia.

If paranoia is a result of anxiety, a doctor may suggest antidepressants or antianxiety medication. However, some of these medications can cause anxiety as a side effect.

In some cases, a change in environment, routine, or care may help ease the symptoms. For example, if a person frequently loses things or thinks that people are stealing things from them, keeping items in the same place or having multiple copies of the items may be helpful.

A consistent, supportive, soothing environment may also help reassure people who are experiencing anxiety, paranoia, or delusions.

A number of strategies can help with managing paranoia and delusions. When interacting with someone who has these symptoms:

  • Do not argue: Delusions are strong beliefs and are unlikely to change in response to logic or reasoning. Arguing may have the opposite effect, causing the person to become more convinced that people are against them.
  • Try not to take offense: Delusions and accusations can be upsetting to watch, but it is important to remember that they come from changes in the brain. The person experiencing them does not know they are not real.
  • Listen: Allow the person to express their feelings and ideas. Pay attention to the emotions they express, even if their facts are incorrect.
  • Acknowledge: To show understanding, repeat what the person has said back to them. For example, “I understand that you do not feel safe. That sounds frightening.”
  • Offer reassurance: If possible, give the person a simple explanation to show why their worries are unfounded. For example, if they are convinced that someone stole something, a caregiver might remind them that the item is in storage.
  • Use distraction: Switching the person’s attention to something else may prevent them from getting increasingly agitated. Try to distract the person with something they enjoy or change the setting by taking them for a walk or a drive.
  • Avoid triggers: Avoid violent imagery on television, which may feel real to the person and make delusions worse.

It is also important to keep the person safe, especially when they are experiencing a delusion or hallucination. Prevent them from wandering around alone and make sure they do not have access to weapons or dangerous objects.

While delusions and hallucinations are potential symptoms of dementia, it is also worth noting that, sometimes, people with dementia become victims of abuse. People refer to this as elder abuse.

Elder abuse can include:

  • neglect
  • physical abuse
  • emotional abuse
  • financial exploitation

People with dementia and memory problems are more vulnerable to elder abuse than others because they are less able to advocate for themselves. It is also easier for abusive people to gaslight them and blame their accusations on their condition.

If a person suspects that elder abuse is taking place, they can consult the National Center on Elder Abuse for advice on how to report it in their state. If a person may be in immediate danger, call 911 or the local emergency number.

Dementia can be difficult to live with and painful to watch in a loved one. When a person becomes paranoid, comforting them can be challenging. Understanding the paranoia as an expression of an underlying need may make it easier to manage.

Treatment can ease anxiety, paranoia, and other common dementia symptoms. These symptoms sometimes signal an underlying medical condition, so it is important to consult a doctor about any new or worsening dementia symptoms.