A diabetic coma could happen when your blood sugar gets too high -- 600 milligrams per deciliter (mg/dL) or more -- causing you to become very dehydrated. It usually affects people with type 2 diabetes that isn’t well-controlled. It’s common among those who are elderly, chronically ill, and disabled. Doctors aren’t sure why, but they think they these people may not realize they’re thirsty or may not be able to get enough to drink. This is a serious condition, and if it isn’t spotted soon and treated quickly, it could be fatal. Knowing the symptoms can help you stay safe.

What Are the Warning Signs?
If you have diabetes and you’ve had a heavy thirst and gone to the bathroom more often than usual for a few weeks, check with your doctor -- especially if your blood sugar isn’t well-controlled. As your body loses more and more water, you may notice:
-- High fever
-- Weakness
-- Drowsiness
-- Altered mental state
-- Headache
-- Restlessness
-- Inability to speak
-- Visual problems
-- Hallucinations
-- Paralysis

Treatment for Diabetic Coma
Severe hypoglycemia
If the blood sugar levels in the blood and brain drop to below normal, the risk of losing consciousness and falling into a diabetic coma is increased. Coma due to severe hypoglycemia is more likely to occur if a patient has taken a large overdose of insulin or other anti-diabetic medications, if alcohol is present in the system while the patient is hypoglycemic or if exercise has reduced the body's supply of glycogen.

Glucagon may be administered to treat hypoglycemia. In healthy individuals, a fall in blood sugar is compensated for by the release of glucagon, which increases blood sugar levels. However, in the diabetic individual, this reaction fails to occur and exogenous glucagon needs to be administered. As an immediate measure, glucose rich foods such as glucose biscuits may be eaten or an injection of glucose solution may be administered. People with diabetes are advised to carry glucose biscuits with them to eat and counteract hypoglycemia as soon as symptoms manifest.

Diabetic ketoacidosis
his is more common among people who are taking insulin for their diabetes. Comas resulting from this condition are induced by a build-up of acidic compounds in the blood called ketones which may occur when the individual has missed an insulin dose. Ketoacidosis may also occur if a person has suffered an acute injury or infection, both of which can raise levels of hormones that counteract the effects of insulin. Anesthesia and surgery can also alter hormone levels in this way. Treatment includes administering isotonic intravenous fluids to correct dehydration and replacing lost electrolytes with sodium, potassium, magnesium and phosphate supplements. Insulin is administered intravenously to reduce blood glucose and reverse ketoacidosis.

Hyperglycaemic hyperosmolar state
Comas that result from HHS are characterized by severe dehydration and very high blood glucose. Treatment includes rapid administration of insulin to bring down blood sugar levels and correction of dehydration using intravenous fluids. Fluids should be given at least 30 to 60 minutes before insulin. Electrolytes may also be replaced as needed and some patients may require antibiotics to clear infection.