My Dad has turned into a monster . So irritable and confused and paranoid. It hurts me to my heart to see him like this at 88 yrs old. I know he would gladly take a medicine that would make him more managerable and pleasant. I know if I was in his shoes I would not want to feel so bad , I would want to feel pleasant. Its cruel to allow someone to feel that way, espescially when you know this is not his norm. I plan to speak with the doctor this week to advocate for him better medical treatment for Mental Health.
Other effects hope this helps.
For Alzheimer's Disease patients like my 83 year old mother, at some point nothing really works, and while I have not given up on medication, I have found that distraction is the best "medicine." I have found a series of things to keep her so occupied that she does not have time to talk about her confusion, delusions, etc. Whether it is an active game, folding towels and clothes, an action movie (which I explain all the way through), petting an animal, or something to keep her "busy." One of her favorites is that I drive her in the car to see the countryside and I play music that I have tested with her to sing along to.
As to medicine my mother currently take Mirtazipine (Remeron) at night, and occasionally a Clonazepam if she is having a bad day. We also try an occasional Trazodone when she is having a bad night. Our doctor took her off Namenda, because she felt it was causing her more cognitive problems than any good it was doing (if any). She is also on the Exelon Patch (which I really haven't seen accomplish anything, but they claim it is slowing her dementia, hard to believe).
I agree it is cruel to allow someone to feel this way. I hope you find some answers for your father, and know there are many of us also struggling with the same issues, and we sympathize with and share your heartbreak over this struggle.