My father is 90 yrs old and has not had a dementia problem. Tonight he woke after a few minutes of sleep and was very confused. At first he was saying paper and cloth don t mix and other things that made no sense to me and he would get frustrated when I didn t understand what he was trying to say. After about 20 minutes he started saying I needed to kill him but it wouldn t hurt because he would already be dead then he would live again. He called me by my mother s name even though I was calling him Dad . He tried to get outside because all the blood would be messy. When I wouldn t let him outside he tried to get a saw and said he was going to cut his own head off. He said he would need some strong people and mentioned my son s name, but when I told him he couldn t get out the doors because they were locked and I couldn t unlock them he believed me and didn t try to get out - just put his hands on the glass and stared outside. I stopped him from going outside or into the work room where tools are, turned most of the lights off and quit talking to him. He wandered around mumbling about where would be best, moved some rugs and lay on the floor. He then wanted a cross to hold and wanted my mother and me to have one too. I believe he fell asleep for a few minutes and then he got up, sat on the couch in his usual place, turned on the light and he seemed normal. Then he turned off the light and went into the bathroom. When I followed him to just outside the bathroom he turned around and said to me, I m alright . He used the bathroom, came out and went to his bedroom and I heard him say, that was strange and I wonder what that was all about . I asked him what was strange and he said We ll talk about it in the morning. It was some kind of delusion . I plan on called his doctor in the morning, but other than sleeping where I can hear if he gets up in the night is there anything I should do? Do you have any idea what caused this?