Hello Steve ......
Sorry to say that the imagination can become very frightening to one with dementia. My Mother was diagnosed with dimentia close to three years ago, but probably had some small signs of it for as much as ten years.
She was, after being released from the hospital in April of 2011 after a fall at home, back home but with a full-time live-in caregiver - as required by the releasing doctor. She was at home for about 16-months - and during that timeframe, she had at least three major episodes at night.
In the most severe episode, she felt someone was in her home wanting to kill her, and the caregiver needed to call me - then call 911 to get her into a hospital ER.
After close to a one month stay in the psychiatric ward of the hospital, that doctor said she could no longer go home under the care of a 24/7 caregiver. He told me she needed to go into a Home that had an on-duty RN full-time on staff.
She has been in that home for the past 15-months now.
One thing to note ......... the new doctor (from that Home) took her off of Namenda shortly after her getting there. In his opinion, the Namenda, at this stage of the Dementia was doing her more harm than good.
She doesn't have the extreme nightr terrors anymore. So I was told by an RN there, the Namenda works well in the early stages of Dementia but not in the later stages.
Check with her doctor!
Rob & Gizzy