Having a plan to respond to high blood glucose is important, because prolonged hyperglycemia can lead to diabetic ketoacidosis (DKA), a life-threatening complication. People with Type 1 diabetes are at higher risk of developing DKA than people with Type 2 diabetes, but it can happen in people with Type 2, particularly if they have a severe infection or injury.
DKA develops when there is not enough insulin in the body to use glucose for energy. When that happens, stored fat is broken down for energy instead, and acid by-products called ketones are created in the process. Ketones build up in the blood and eventually spill into the urine. The combination of high blood glucose, high blood ketones, and dehydration can lead to coma or even death.
It is recommended that you check your blood or urine for ketones if your blood glucose is over 240 mg/dl, if you are sick or have an infection, if you are under a lot of stress, if you have lost weight and don’t know why, or if you are not feeling well (even if your blood glucose is not elevated). One of the most common signs of DKA is having a sweet, fruity odor to your breath. Other signs include nausea, abdominal pain, flushed skin, rapid breathing, loss of appetite, or unconsciousness. The people you spend time with regularly should be aware of the warning signs of DKA since they can easily be mistaken for the flu.
Hypoglycemia. Hypoglycemia is when your blood glucose is too low. It can happen if you skip a meal or snack, eat a meal or snack later than usual, eat less than usual, exercise more than usual, take too much diabetes medicine, or drink alcohol on an empty stomach. Your body will usually give you warning signs of low blood glucose, which may include feeling tired, hungry, sweaty, shaky, dizzy, grouchy, or confused.
When you experience these symptoms, it is important to respond quickly. If you can check your blood glucose level with your meter, do so. If you can’t get to your meter quickly, it’s safer to go ahead and treat yourself for hypoglycemia than to wait until you can check with your meter. If your blood glucose level is 70 mg/dl or lower, eat or drink something containing 15 grams of carbohydrate, and recheck in 15–20 minutes. If your blood glucose has not risen in that time, eat or drink another 15 grams of carbohydrate. If it has risen by at least 30 mg/dl and is above 70 mg/dl, you do not need to eat or drink more. However, if it is almost time to eat a meal, go ahead and eat the meal.
Some people have a higher risk of developing hypoglycemia than others. Those at higher risk include anyone who uses insulin and anyone who takes one of the following drugs: glimepiride (brand name Amaryl), glipizide (Glucotrol and the combination drug Metaglip), or glyburide (DiaBeta, Glynase, Micronase, and the combination drug Glucovance). People who take multiple medicines for Type 2 diabetes are also at a higher risk of hypoglycemia. People who control their Type 2 diabetes with diet and exercise or who take only metformin (Glucophage and other brands) are at low risk for hypoglycemia.
Anyone who is at risk of developing hypoglycemia is advised to carry a source of 15 grams of carbohydrate in case of low blood glucose. Portions of food and drink that contain 15 grams of carbohydrate include 3 regular-size marshmallows; 3–5 LifeSavers, sugar cubes, or glucose tablets; and half a cup (4 ounces) of fruit juice or regular (nondiet) soft drink.
Also in this article:
Continuous Glucose Monitoring
Blood Glucose Targets
Twice-A-Day Monitoring Schedule
Average Blood Glucose











