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When Your Blood Sugar Is Too High or Too Low

Sometimes, no matter how hard you try to keep your blood sugar in the range your doctor has advised, it can be too high or too low. Blood sugar that is too high or too low can make you very sick. Here's how to handle these emergencies.

What You Need to Know about High Blood Sugar

If your blood sugar stays over 240, it is too high. High blood sugar usually comes on slowly. It happens when you don't have enough insulin in your body. High blood sugar can happen if you miss taking your diabetes medicine, eat too much, or don't get enough exercise. Sometimes, medicines you take for other problems may cause high blood sugar. Be sure to tell your doctor about other medicines you take.

This chart shows the ranges of blood sugar.

Having an infection or being sick or under stress can also make your blood sugar too high. That is why it is very important to test your blood and keep taking your medicine (insulin or diabetes pills) when you have an infection or are sick.

Your blood sugar may be too high if you are very thirsty and tired, have blurry vision, are losing weight fast, and have to go to the bathroom often. Very high blood sugar may make you feel sick to your stomach, faint, or throw up. It can cause you to lose too much fluid from your body.

Testing your blood sugar often, especially when you are sick, will warn you that your blood sugar may be rising too high. If your blood sugar stays over 300 when you check it two times in a row, call your doctor. You may need a change in your insulin shots or diabetes pills, or a change in your meal plan.

If you are not sick and do not have ketones in your urine, going for a slow walk or some other easy exercise may lower your blood sugar.

What You Need to Know about Low Blood Sugar

If your blood sugar drops too low, you can have a low blood sugar reaction, called hypoglycemia. A low blood sugar reaction can come on fast. It is caused by taking too much insulin, missing a meal, delaying a meal, exercising too much, or drinking too much alcohol. Sometimes, medicines you take for other health problems can cause blood sugar to drop.

A low blood sugar reaction can make you feel shaky, mixed up, unhappy, hungry, or tired. You may sweat a lot or get a headache. Your legs may shake. If your blood sugar drops lower, you can get very confused, sleepy, or irritable, or you may pass out or have a seizure.

Treat low blood sugar quickly. If you have signs of low blood sugar, eat or drink something that has sugar in it. Some things you can eat are hard candy, sugar-sweetened soda, orange juice, or a glass of milk. Special tablets or gel made of glucose (a form of sugar) can be used to treat low blood sugar. You can buy these in a drug store. Always have some of these items handy at home or with you when you go out in case your blood sugar drops too low. After treating a low blood sugar reaction, eat a small snack like half a sandwich, a glass of milk, or some crackers if your next meal is more than 30 minutes away.

WebMD Public Information from the U.S. National Institutes of Health

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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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