One of these potential emergencies is ketoacidosis -- sustained high blood sugar that produces toxins, ketones, in your body.
What can happen: Diabetic ketoacidosis, or DKA, is a serious and possibly life-threatening condition that results from not having enough insulin. A lack of insulin in your body means that the glucose in your blood cannot be used for energy. The body then looks for an alternate form of energy, such as stored fat. But as fat is broken down, it creates a toxic waste product known as ketones, which can poison the body.
Ketoacidosis can also accompany sickness. It’s important to test for ketones regularly when you are ill. Ketone testing is easy and can be done at home with the use of urine strips. 
Symptoms of DKA include:
- nausea and vomiting
- a rapid and weak pulse
- abdominal pain
- breath that has a fruity odor
- labored breathing
- low blood pressure
How to respond: When any of the above symptoms are accompanied by 2 or more glucose readings over 300 mg/dl, you should contact your doctor. When vomiting is present, ketoacidosis can progress quickly. The immediate treatment involves rehydration of lost fluids and giving insulin. When you are ill, check for ketones every 4 to 6 hours.
Learn more about other diabetes emergencies you should be prepared for:
Source:
Ketoacidosis. American Diabetes Association. Accessed March 13, 2009. http://www.diabetes.org/type-1-diabetes/ketoacidosis.jsp
