Medication for confusion/agitation

My dad recently started declining mentally and has days when he is very agitated and confused. My mum took him to see a psychiatrist last week who prescribed tiapride. He almost stopped walking from the day he started taking it and after my mum told me what he was put on and I checked it, I realised that they gave him medication that blocks dopamine receptors! 

I know prescribing any kind of medication for him is difficult but I was wondering if anyone (or their family member) are taking anything that seems to help without too many side effects? I was wondering about diazepam and I know it can also affect Parkinson's but not in the same drastic way as Tiapride. 

I am also trying to get my mum to take him to be tested for UTI but that's another story...