High Blood Sugar

Definition and Symptoms

High blood sugar, or hyperglycemia, occurs when the body has too much food or glucose, or too little insulin. The following are all potential reasons that a person with type 1 diabetes (T1D) might have high blood sugar:

  • Not enough insulin taken
  • Eating more than usual
  • Eating earlier than usual
  • Eating food with higher glucose content without injecting extra insulin
  • Injecting insulin at a site on the body where the absorption rate is slower
  • Missing or skipping an insulin dose
  • A clog in insulin pump tubing
  • Less exercise than normal
  • Stress
  • Illness or injury
  • Other hormones
  • Medications

High blood sugar generally does not immediately put the person with type 1 diabetes in danger. However, high blood sugar levels over long periods of time can lead to serious complications such as heart disease, blindness, kidney failure, and amputation.

Very high blood sugar levels can lead to diabetic ketoacidosis (DKA), or a “diabetic coma.” DKA occurs when the cells can’t get the energy they need from glucose, and the body begins to burn fat and body tissue for energy. This causes the release of byproducts called ketones, which are dangerous when released at high levels. Ketones become like poison to the body and are passed in the urine as they build up in the blood.

A person with T1D and high blood sugar may exhibit one or more of the following symptoms:

  • Thirst (dehydration)
  • Frequent urination
  • Blurry vision
  • Stomach pain
  • Increased hunger
  • Nausea
  • Drowsiness, lethargy, exhaustion
  • Confusion
  • Sweating
  • Fruity, sweet, or wine-like odor on breath
  • Vomiting
  • Inability to concentrate
  • Weight loss (a longer-term symptom) that eventually leads to coma

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What to Do About High Blood Sugar Levels

The following recommendations are general treatments for high blood sugar. Specific actions–such as giving additional insulin–should be determined by the adult with type 1 diabetes (T1D), physician, or parents (for a child).

1. If blood test results are slightly above normal:

  • Continue regular activity
  • Drink water or sugar-free drinks
  • Monitor blood sugar levels by checking regularly
  • Chart blood glucose test results

2. If blood test results are moderately high:

  • Don’t engage in strenuous exercise
  • Drink water or sugar-free drinks
  • Inject additional insulin if instructed by physician or parents
  • Monitor blood sugar levels by checking regularly
  • Chart blood glucose test results

3. If blood test results are very high:

  • Don’t engage in strenuous exercise
  • Drink water or sugar-free drinks
  • Inject additional insulin if instructed by parents or physician
  • Test ketone levels if advised by parents or physician. If high, contact parent or physician immediately
  • Monitor blood sugar levels by checking regularly
  • Chart blood glucose test results

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