He gets very angry when told he is at home & this is where he/Mom have lived for 68 yrs. He continually says NO he knows he lives at 1442 Louis st & this is not my home. We even put him in car take him riding & he then says " Take me home to 1442 Louis st why are you out riding around" . It is very frustrating as no answer satisfies him. This is from noon until about 5:00 p.m. then he go back to being him old self . What is going on ??
My husband wanted to go home often during his first year of dementia. It did absolutely no good to try to convince him that he was at home. I wasted a lot of energy on that.
So, don't tell him he is at home. Tell him, "I'm afraid I can't take you right now. Let's try for after dinner." or "The road is blocked off for sewer work. We'll have to try tomorrow." or "The bug exterminators are there today. We'll have to stay away for a few days." Do not agree to take him home, but give him some excuse. Repeat it as necessary. Hope he forgets about it by evening! Also try a distraction. "We might be able to go home later, but for now let's see if there is any ice cream in the freezer."
I wonder if he'd like a nap after lunch? Or some activity scheduled for that time? "Well, we can't make a trip right now, but this is your time to work on the jigsaw puzzle for a half an hour."
It might help to find out what he wants to do at home. (He may not know, though.) Try to provide what he wants. "I want to take a nap in my own bed!" I'm sorry we can't go right now, but I can take you to a very comfortable bed here where you can take a nap.
One theory is that what dementia folks really want when they long to "go home" is to go back to a time when things felt normal to them, when they were healthy, and understood their environment. There is no way you can take them "home" in this sense. Make excuses and redirect.
If you can find activities that can calm him down during this all the better but I would talk to his Dr. about it. Maybe there's something your Dr. can prescribe that will help your dad. Not to sedate him but to shave the edge off of his anxiety. Five hours is a long time to be upset. If the Xanax didn't help maybe Ativan will.
As frustrating as it is for you and your mom your dad is upset too and that can't feel good. I hope you find a solution. You may find that one day it just stops. Dementia is progressive and while your dad will probably continue to show signs of progression this particular situation may stop altogether. Probably to be replaced by something else but maybe the next obsession will be something a little easier to handle.
My Mom also takes Seroquel which helps withe the sundowning tremendously. Some nights I also have to give her .25 mg of Xanax, though not often. A quarter of a mg of Xanax is a very small dose. You may want to talk to his doctor about increasing it or trying something different altogether. Did the Xanax seem to work better when he first started taking it? It's effectiveness may be wearing out for him.