High and Low Blood Sugar

Managing The Ups and Downs

Woman Tests Blood Sugar Which Is High
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High and low blood sugar are a daily part of living with diabetes. There will be plenty of days when your glucose readings seem out of control. Instead of panicking, your best strategy is to learn all you can about how to prevent these extremes and properly treat them when they occur.

Low Blood Glucose

When your glucose is considered low, it is called hypoglycemia (sometimes referred to as an insulin reaction).

If you take too much insulin, miss a meal or snack, or exercise more than expected, you might experience a low blood sugar reaction. Low glucose levels occur from time to time for everyone who has diabetes. Your best strategy for avoiding hypoglycemic reactions is to quickly recognize the symptoms.

You may have one or more of these symptoms at any given time. If you feel any of these symptoms, your first response should be to check your blood glucose. If your reading is below what your doctor recommends, then treat it immediately.

Treating a Hypoglycemic Reaction

The fastest way to raise your blood glucose is to eat or drink something that has a high concentration of sugar, such as:

  • ½ cup of fruit juice
  • 5-6 pieces of hard candy
  • 3 glucose tablets (specifically designed for treating insulin reactions)

After you’ve treated your low blood glucose, wait 15 minutes and check your blood again to ensure that your glucose levels are greater than 80 mg/dl before resuming your activity.

To be adequately prepared for treating hypoglycemic reactions, you should always carry some form of sugar product with you that is easily accessible.

Preventing Hypoglycemia

The best way to prevent low glucose reactions is to test your blood regularly, learn to recognize the early symptoms, and treat it immediately before symptoms worsen.

High Blood Glucose

When your glucose levels are higher than normal, it is called hyperglycemia. Hyperglycemia can be caused by missing an insulin injection, eating more than what your meal plan allows or not getting physical activity. Sickness also can cause a rise in your blood sugar. Hyperglycemia occurs from time to time in all people who have diabetes and the goal is to minimize the amount of time it remains high.

When your blood glucose is low, symptoms are usually evident. But when your glucose levels are high, it may not always be as easy to recognize the most common symptoms, which are frequent urination and thirst. If you suspect that your glucose is high, the best way to confirm this is to check your blood glucose. Too often, people with diabetes mistakenly believe they can accurately discern when their glucose levels are high based upon how they feel. This can lead to sustained high blood sugar that can, when extreme, cause dangerous health problems like ketoacidosis, a toxic state that results when body fat is used in place of glucose for fuel. When glucose is elevated over a long period of time, it significantly increases the risk of several long-term health complications that affect the eyes, nerves, blood vessels, and kidneys.

Treating Hyperglycemia

Periodic elevation of your glucose is normal and may be treated by exercising or reducing the amount of food you eat at a given time. Chronically high glucose levels will require you to consult your doctor to determine if adjustments need to be made to your insulin doses. It may also be helpful to talk with your dietician to assess whether your meal plan needs to be updated. Routine visits with a dietician are especially important for adjusting nutritional and caloric needs for growing children.

Preventing Hyperglycemia

Your best strategy for preventing high glucose levels is to:

  • Test your blood often
  • Follow the meal plan outlined by your dietician
  • Exercise regularly
  • Take your insulin as prescribed


Hypoglycemia. American Diabetes Association. http://www.diabetes.org/type-1-diabetes/hypoglycemia.jsp

Hyperglycemia. American Diabetes Association. http://www.diabetes.org/type-1-diabetes/hyperglycemia.jsp 404

Hypoglycemia/Hyperglycemia. National Diabetes Education Program. http://www.ndep.nih.gov/diabetes/youth/youth_FS.htm#Hypoglycemia 500