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Diabetes-Related High and Low Blood Sugar Levels - Topic Overview

High blood sugar occurs when the sugar (glucose) level in your blood rises above normal. Eating too many calories, missing medicines (insulin or pills), or having an infection or illness, injury, surgery, or emotional stress can cause your blood sugar to rise.

High blood sugar usually develops slowly over a period of hours to days. But missing a dose of insulin can cause a rapid rise in blood sugar levels. Blood sugar levels just above your target range may make you feel tired and thirsty. If your blood sugar level stays higher than normal for weeks, your body will adjust to that level, and you may not have as many symptoms of high blood sugar.

Unless you don't monitor your blood sugar regularly or you don't notice the symptoms of high blood sugar, you usually will have time to treat high blood sugar so that you can prevent high blood sugar emergencies. Three things can help you prevent high blood sugar problems:

  • Test your blood sugar often, especially if you are sick or are not following your normal routine. You can see when your blood sugar is above your target range, even if you don't have symptoms of high blood sugar such as increased thirst, increased urination, and fatigue. Then you can treat it early, preventing an emergency.
  • Call your doctor if you have frequent high blood sugar levels or if your blood sugar level is consistently staying above your target range. Your medicine may need to be adjusted or changed.
  • Drink extra water or noncaffeinated, non-sugared drinks so you will not be dehydrated. If your blood sugar continues to rise, your kidneys will increase the amount of urine produced, and you can become dehydrated.

Complications of high blood sugar can cause serious problems, including coma and death. Over time, high blood sugar can damage your eyes, heart, kidneys, blood vessels, and nerves.

Low blood sugar occurs when the sugar (glucose) level in your blood drops below what your body needs. Not eating enough food or skipping meals, taking too much medicine (insulin or pills), exercising more than usual, or taking certain medicines that lower blood sugar can cause your blood sugar to drop rapidly. Do not drink alcohol if you have problems recognizing the early signs of low blood sugar.

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70-130
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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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