What can happen when my blood sugar level has reached over 600?

It depends...: If you are type1, then this is approaching danger--diabtetic ketoacidosis..Seek care asap. If type 2 and you have very high sugar regularly, you dont need emergency care, but definitely consult with your doc asap to help with safely lower your sugar and better manage your diabetes. If you have dizziness, blurry vision, weakness, nausea, excessive urination, thirst etc..Call ems.. Asap.

Uncontrolld diabetes: The consequences of uncontrolled diabetes include immediate problems such as dehydration and coma. Long term effects include eye problems such as glaucoma, cataracts, or retinopathy resulting in blindness, kidney disease, peripheral nerve damage, foot infections and ulcers possibly resulting in leg amputation, and blocked arteries resulting in heart disease, stroke, or peripheral arterial disease.

You could die: Severe hyperglycemia (high blood sugar) can be associated with a variety of complications. Type 1 (insulin dependent): can get severely abnormal chemistries (ketoacidosis), altered mental status, diabetic coma, dehydration, infection, kidney failure. Type 2 (non Insulin dependent): no ketoacidosis, but the other complications. Symptoms of excess thirst, urination, eating-xs glucose in urine.