When someone who has dementia is still able to argue, protest, deny,……etc. it’s particularly frustrating and very stressful. It’s often referred to as Resistance to care. It requires a lot of patience, planning, tenacity and support. If his doctor regularly treats patients with dementia then he knows how things go. He can recommend meds for agitation and anxiety.

I would keep in mind that just because the doctor tells him to not drive, he may still do it. One, because his judgment is poor and he can’t reason the negatives of driving against doctor orders and two, because he will forget. So, even if DMV takes his license, he may still drive because of the same reasons. So someone must ensure he doesn’t. It’s not negotiable no matter how upset he may be. I’d get a legal consult with an attorney for advice on how to get legal control and be able to legally remove the car, sell, etc. against his wishes if necessary. When someone is unpredictable, disoriented and uncooperative, it becomes a safety concern. Have you considered an assessment to see what level of care he needs?