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From the National Institutes of HealthNational Institutes of Health

High blood sugar

High blood sugar occurs when your body makes too little insulin or when your body is not able to use insulin the right way. Insulin is a hormone that helps the body use glucose (sugar) for energy. Insulin is made by the pancreas.

High blood sugar is also called high blood glucose or hyperglycemia.

Symptoms of High Blood Sugar

Symptoms of high blood sugar can include:

  • Being very thirsty
  • Having blurry vision
  • Having dry skin
  • Feeling weak or tired
  • Needing to pee a lot

You may have other, more serious symptoms if your blood sugar becomes very high.

What to Think about When Your Blood Sugar Is High

High blood sugar can harm you. If your blood sugar is high, you need to know how to bring it down. Here are some questions to ask yourself if your blood sugars are high:

Are you eating correctly?

  • Are you eating too much? Have you been following your diabetes meal plan?
  • Did you have a high-fat or high-fiber meal?

Are you taking your diabetes medicines correctly?

  • Has your doctor changed your medicines?
  • If you take insulin, have you been taking the correct dose?
  • Are you afraid of having low blood sugar? Is that causing you to eat too much or take too little insulin or other diabetes medicine?
  • Have you injected insulin into a scar or overused area? Have you been rotating sites?

What else has changed?

  • Have you been less active than usual?
  • Do you have a cold, the flu, or another illness?
  • Have you had some stress?
  • Have you been checking your blood sugar ?
  • Have you gained weight?

Preventing High Blood Sugar

When you have diabetes, you will learn to use diet, exercise, and diabetes medicines or insulin to prevent high blood sugar levels.

You and your doctor will:

If your blood sugar is higher than your goals for 3 days and you do not know why, check your urine for ketones. Then call your doctor or nurse.

Alternate Names

Hyperglycemia - self-care; High blood glucose - self-care

References

American Diabetes Association. Standards of medical care in diabetes -- 2013. Diabetes Care. 2013; 36 Suppl 1:S11-S66.

Update Date: 12/11/2012

Updated by: Nancy J. Rennert, MD, Chief of Endocrinology & Diabetes, Norwalk Hospital, Associate Clinical Professor of Medicine, Yale University School of Medicine, New Haven, CT. Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.

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