You may want to get a MRI of his brain and his spin to make sure nothing is majorly wrong...It can be so many things.
I can almost say he is deficeint in minerals and insulin resistance...maybe weakened adrenals but I these symptoms can be so many things I am sure...I would let some DR's so blood work and a scan to make sure like I said he is not seriously ill. I can imagine the fear he and your family has, this can actually making things worse on him with stress.
I pray you can get some answers for him..Big Hugs to you guy.