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High & Low Blood Glucose (Sugar) Reactions HF#4346



One goal of diabetes care is to keep blood glucose (sugar) levels within a “normal” range. Both high and low blood glucose levels can mean that you won’t feel the best, but it could also mean serious complications. This handout will tell you more about causes, symptoms, and treatment of high and low blood glucose levels, as well as how to prevent them.

 

Low Blood Glucose (Hypoglycemia)

 

Low blood glucose (below 70 mg/dL) is also called hypoglycemia.

 

Causes

  • Too much insulin or diabetes pills (Talk with your health care team if you think this is the cause.)
  • Late or skipped meal
  • Smaller than usual meal
  • More activity than usual
  • Alcohol intake without food
  Symptoms
  • Shaky or anxious
  • Sweaty or clammy
  • Light-headed or weak
  • Blurry vision
  • Hungry
  • Irritable or confused

 

-  Get to know YOUR symptoms of low blood glucose and respond quickly.

-  Never ignore symptoms of low blood glucose.

-  If low blood glucoses are not treated quickly, you may lose consciousness.

 

Treatment Options

 

If your glucose level is below 70 mg/dL and you can swallow safely, take one of these choices:

 

  • 4 oz. juice
  • 4-6 oz. (non-diet) regular soda
  • 3-4 glucose tablets (chew them)
  • “Soft” chewable candy (amount varies by candy choice)
  • 1 tube of glucose gel
  • 1 small tube of cake frosting
  • Other: __________________

 

-  Each choice above contains about 15 grams of carbohydrate. Eating or drinking one of these choices should raise your blood sugar about 50 mg/dL.

-  Check your blood glucose 15 minutes after treatment. If your glucose is still below 70 mg/dL, repeat the treatment every 15 minutes until your glucose is above 70 mg/dL. Consider checking your glucose 60 minutes after treatment to be sure the glucose is stable.

 

-  Call 911 if you feel too sick to eat or if glucose levels stay below 70 mg/dL after 30 minutes.


 

High Blood Glucose (Hyperglycemia)

 

High blood glucose is also called hyperglycemia.

 

Causes

  • Missed dose of insulin or diabetes pills
  • Not enough insulin or diabetes pills (Talk with your health care team if you think this is the cause.)
  • Less activity than usual
  • Overeating
  • Illness (cold, flu, infection)
  • Stress (physical or emotional)

 

Symptoms

  • Thirst
  • Frequent urination
  • Nausea/vomiting
  • Unexplained weight loss
  • Slow healing
  • Frequent infections
  • Fatigue
  • Blurry vision


-  Many people do not have symptoms of high blood glucose until levels are very high.

-  If not treated, high blood glucose levels can be life-threatening.

 

Treatment Options

 

  • Insulin is often used to treat high blood glucose levels. If you do not use insulin, talk with your health care team about what to do about high blood glucose levels.
  • It is not always best to exercise or to eat less to lower your glucose levels. Discuss this with your health care team.
  • If your blood glucose is more than 250 mg/dL and you are sick, follow sick day guidelines. (See Health Facts for You: Sick Day Guidelines for Type 1 Diabetes or Sick Day Guidelines for Type 2 Diabetes)

 

Preventing Hypoglycemia and Hyperglycemia

 

  1. Know what causes low and high blood glucose levels for you. Take steps to prevent the things that put you at risk for low and high blood glucose levels.
  2. Take your insulin or oral medications as scheduled. If you think the doses are a cause of your low or high blood glucose levels, talk with your health care team about making changes.
  3. Follow your prescribed meal plan. Do not skip meals and avoid overeating.
  4. Test your glucose levels often. Talk to your doctor or nurse about what is best for you. Keep a written log book of your results. Watch for patterns of high or low glucose levels.

 

Informing Others

 

Always wear identification that is easily seen by others such as a Medic-Alert bracelet or necklace.  Carry a wallet card that states that you have diabetes.  Include your current medicine and/or insulin dose.

 



The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.

Last Updated: 01/27/2010

Copyright © 01/27/2010 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#4346

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