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Problems from high blood sugar levels

High blood sugar levels (hyperglycemia) occur when your blood sugar (also called glucose) is higher than your body needs to function normally. High blood sugar levels can cause both immediate and long-term problems.

Immediate problems

Diabetic ketoacidosis (DKA) is a life-threatening blood chemical (electrolyte) imbalance that develops in a person with diabetes when the cells do not get the sugar they need for energy. As a result, the body breaks down fat instead of glucose and produces and releases substances called ketones into the bloodstream.

People with type 1 diabetes and some people with type 2 diabetes have an increased risk for DKA if they do not take enough insulin, have a severe infection or other illness, or become severely dehydrated.

Symptoms of diabetic ketoacidosis include:

  • Flushed, hot, dry skin.
  • A strong, fruity breath odor.
  • Loss of appetite, abdominal pain, and vomiting.
  • Restlessness.
  • Rapid, deep breathing.
  • Confusion.
  • Drowsiness or difficulty waking up. Young children may lack interest in their normal activities.

Severe diabetic ketoacidosis can cause difficulty breathing, brain swelling (cerebral edema), coma, or death. Prompt medical evaluation and treatment are needed if symptoms of diabetic ketoacidosis are present.

Treatment involves giving insulin and fluids through a vein and closely monitoring and replacing electrolytes.

Long-term complications

Your risk of complications increases if your blood sugar levels are often above your target level. Persistently high blood sugar can damage blood vessels and nerves.

  • Damage to large blood vessels (macrovascular disease) can lead to a buildup of plaque, increasing your risk of coronary artery disease, heart attack, and stroke.
  • Damage to small blood vessels (microvascular disease) can lead to loss of vision, kidney disease, and nerve problems throughout the body.
  • Nerve damage (diabetic neuropathy) can decrease or completely block the movement of nerve impulses or messages through organs, legs, arms, and other parts of the body. Nerve damage can affect your internal organs and your ability to feel pain when you are injured.

If your episodes of high blood sugar levels are occurring more frequently, a visit to your doctor is needed.

By Healthwise Staff
Primary Medical Reviewer William H. Blahd, Jr., MD, FACEP - Emergency Medicine
Specialist Medical Reviewer H. Michael O'Connor, MD - Emergency Medicine
Current as of April 25, 2012

WebMD Medical Reference from Healthwise

Last Updated: April 25, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

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