your mother needs to be seen by a psychiatrist so that she can be properly evaluated. yes there are medications that may help but these will need to be prescribed for her by a clinician that is very familiar with the type of dementia that she has and someone who knows her complete medical history.
my mother has demtia and is hearing things like a radio broadcast about my fathers passing. my father passed away on march 14 2015 of a blood infection. the day after he died my mother started accusing my niece of shooting him in the head and is still talking about it with more detail. i am struggling with what to say and do. is there medication she can take to help with these thoughts? i feel like she is not eating or sleeping well. . what can i do to help her?