For many years I thought my mother's dementia was caused by strokes, but eventually she was told a medication she'd been prescribed for decades was strongly implicated. While the medication was discontinued, much damage had already been done, and could not be reversed.
I recommend careful review of the medications your father is on, and second opinions regarding them.
I hope you are able to attain a better outcome than I was. My mother passed last year.
It is the pharmaceuticals... people are too trusting of their doctors. Doctors just do not do their due diligence; biggest problem i can see is that everything is treated with a pill.. It's always full on pharmaceuticals never a holistic view point, or natural remedies.. They say the average payoff for a Doctor is an extra $40,000 a year. That is the hook, that catches them... Thank you for sharing your story. I am sorry to hear of your loss.. No one should have to leave this World in that way.