Hi, I'm worried for my diabetic father in law, He is obese (140kg) and has type 2 diabetes. He has seen a chinese medicine "doctor" and following his diet despite many calls not to. On advice of this pseudo-doctor, he is not taking his insulin (he usually takes 3 shots a day) and is not eating or drinking anything except for a "herbal drink" (herbs unknown)- it is a non-sugary drink. How long would it take before the onset of Hyperosmolar hyperglycemic nonketotic syndrome (HHNS) or Diabetic ketoacidosis (DKA)? He's VERY stubborn and won't tell me any side-effects that he gets so how soon should I call an ambulance (he started fasting this morning, its 1:02pm now)

Call an ambulance at any notice of cognitive changes, mood changes, or sensory changes.

Altered mental status would be considered a medical emergency.