Dementia steady damage parts of the brain. For this reason, people with dementia may experience delusions and hallucinations. This can lead to paranoid dementia and mistrust of others, including loved ones.

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

Potential causesTrusted Source 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