Glucose is blood sugar (hyperglycemia) comes from diabeties often, but can occur with other reasons, when glucose is to high someoenes sugar raises. Often this can lead to a diabetic coma, fatigue, vomiting, hospitalization, and even death if serious enough, from to high sugar. Many things can happen after this, and a lot are serious.
on the flip side (hypoglycemia) if sugar gets to low, confusion, fainting, vomiting, and nausea occur, as well as comas, and death if serious enought.