My husband is having dizziness and difficulty walking, plus mental confusion. He was seen in the ER yesterday and they found after blood testing and urine testing everything was normal. They even checked his pacemaker and found nothing. He has diabetes and was very dehydrated. He was much better after an iv and a sandwich. He was able to walk out on his own and to eat dinner. However this morning he went back to sleep and got up at 5pm with the same symptoms. Could this be from dehydration? How much water should he be drinking a day? Dose seltzer water work the same, or is the carbonation be a problem?