Signs of Diabetic Coma

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Diabetic coma is a frightening complication of type 1 diabetes. It can occur when blood sugars are either too high, due to fluid loss and dehydration, or when blood sugar levels drop too low from hypoglycemia. Needless to say, this is a scary condition that can lead to brain damage or death. It goes without saying it’s important to recognize the signs of diabetic coma so that treatment can begin as soon as possible.

Signs of Diabetic Coma in Type 1 Diabetics

The most common cause of diabetic coma in type 1 diabetics is elevated blood sugars and ketoacidosis. When a type 1 diabetic has insufficient insulin, a ketotic state can develop as fatty acids from fat stores are broken down to form ketone bodies to fuel the brain. Even though there’s too much glucose in the bloodstream, it can’t get into cells to be used as an energy source due to lack of insulin.

When glucose and ketone levels are high in the bloodstream, they spill out into the urine causing water, sodium and potassium to follow. This leads to dehydration and deficiencies in sodium and potassium and other electrolytes. This state of dehydration causes many of the signs of diabetic coma in type 1 diabetics.

What are the signs of diabetic coma in type 1 diabetics? Because of the dehydration, some of the early signs of an impending diabetic coma are excessive thirst, increased need to urinate (due to the glucose spilling into the urine along with water) and changes in mental status. A person with early diabetic coma can appear disoriented, restless or difficult to arouse. Because of the ketone bodies in their bloodstream, they may have a fruity odor to their breath and may be nauseated or vomit. The dehydration also causes the pulse rate to increase and breathing to become more rapid.

When Diabetic Coma is Due to Hypoglycemia

If a person with type 1 diabetes develops diabetic coma from hypoglycemia or very low blood sugars, they may appear nervous, jittery, anxious, shaky, sweaty and confused prior to becoming unresponsive and slipping into a coma. The life-saving treatment is to restore their blood sugar levels to normal as quickly as possible.

What’s Causing the Diabetic Coma?

It’s critical to know what’s causing the signs of diabetic coma. Is the blood sugar too high or too low? Not giving glucose to a type 1 diabetic with diabetic coma due hypoglycemia can quickly lead to permanent brain damage or death. A blood sugar level will distinguish between the two causes of diabetic coma.

Signs of Diabetic Coma: The Bottom Line?

It’s obviously important to recognize and quickly act on the early signs of diabetic coma. Not to do so could have serious long-term consequences in the form of brain damage or death. Be familiar with its signs and act on them as quickly as possible. It could save the life of someone with diabetes.


Merck Manual. Eighteenth edition. 2006.

University of New Mexico Press.Diabetic Coma: Ketoacidotic and Hyperosmolar. 1981.