Diabetic coma

A diabetic coma is a life-threatening diabetes complication that causes unconsciousness.

If you have diabetes, dangerously high blood sugar (hyperglycemia) or dangerously low blood sugar (hypoglycemia) can lead to a diabetic coma.

If you lapse into a diabetic coma, you're alive — but you can't awaken or respond purposefully to sights, sounds or other types of stimulation. Left untreated, a diabetic coma can be fatal.

The prospect of a diabetic coma is scary, but fortunately you can take steps to help prevent a diabetic coma. Start by following your diabetes treatment plan.

Symptoms Causes Risk factors Complications Prevention

Before developing a diabetic coma, you'll usually experience signs and symptoms of high blood sugar or low blood sugar.

High blood sugar (hyperglycemia)

If your blood sugar level is too high, you may experience:

  • Increased thirst
  • Frequent urination
  • Fatigue
  • Nausea and vomiting
  • Shortness of breath
  • Stomach pain
  • Fruity breath odor
  • A very dry mouth
  • A rapid heartbeat

Low blood sugar (hypoglycemia)

Signs and symptoms of blood sugar level may include:

  • Shakiness or nervousness
  • Fatigue
  • Sweating
  • Hunger
  • Nausea
  • Irritability
  • An irregular or racing heartbeat
  • Difficulty speaking
  • Confusion

Some people develop a condition known as hypoglycemia unawareness and won't have the warning signs that signal a drop in blood sugar.

If you experience any symptoms of high or low blood sugar, test your blood sugar and follow your diabetes treatment plan based on the test results. If you don't start to feel better quickly, or you start to feel worse, call for emergency help.

When to see a doctor

A diabetic coma is a medical emergency. If you feel extreme high or low blood sugar symptoms and think you might pass out, call 911 or your local emergency number. If you're with someone with diabetes who has passed out, call for emergency help, and be sure to let the emergency personnel know that the unconscious person has diabetes.

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