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Diabetes-Related High and Low Blood Sugar Levels
Diabetes-related blood sugar levels
When you have diabetes, you may have high blood sugar levels (hyperglycemia) or low blood sugar levels (hypoglycemia) from time to time. A cold, the flu, or other sudden illness can cause high blood sugar levels. You will learn to recognize the symptoms and distinguish between high and low blood sugar levels. Insulin and some types of diabetes medicines can cause low blood sugar levels.
Learn how to recognize and manage high and low blood sugar levels to help you avoid levels that can lead to medical emergencies, such as diabetic ketoacidosis or dehydration from high blood sugar levels or loss of consciousness from severe low blood sugar levels. Most high or low blood sugar problems can be managed at home by following your doctor''s instructions on the use of insulin or diabetes medicines, diet, and exercise. Home blood sugar testing will help you determine whether your blood sugar is within your target range. If you have had very low blood sugar, you may be tempted to let your sugar level run high so that you do not have another low blood sugar problem. But it is most important that you keep your blood sugar in your target range. You can do this by following your treatment plan and checking your blood sugar regularly.
Sometimes a pregnant woman can get diabetes during her pregnancy. This is called gestational diabetes. Blood sugar levels are checked regularly during the pregnancy to keep levels within a target range.
Children who have diabetes need their parents''t monitor your blood sugar regularly or 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.
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 (hypoglycemia)
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.
People who lose weight or develop kidney problems may not need as much insulin or other medicines as they did before they lost the weight or developed kidney problems. Their blood sugar may drop too low. Be sure to check your blood sugar often when your body goes through changes.
- If your blood sugar level drops just slightly below your target range (mild low blood sugar), you may feel tired, anxious, weak, shaky, or sweaty, and you may have a rapid heart rate. If you eat something that contains sugar, these symptoms may last only a short time. If you have diabetes, you may not always notice symptoms of mild low blood sugar. This is called hypoglycemia unawareness. If your blood sugar is well controlled and does not change much during the day, you may have an increased risk for hypoglycemic unawareness.
- If your blood sugar level continues to drop (usually below 40 mg/dL), your behavior may change, and you may feel more irritable. You may become too weak or confused to eat something with sugar to raise your blood sugar level. Anytime your blood sugar drops below 50 mg/dL, you should act whether you have symptoms or not.
- If your blood sugar level drops very low (usually below 20 mg/dL), you may lose consciousness or have a seizure. If you have symptoms of severe low blood sugar, you need medical care immediately.
You may have symptoms of low blood sugar if your blood sugar drops from a high level to a lower level. For example, if your blood sugar level has been higher than 300 mg/dL for a week or so and the level drops suddenly to 100 mg/dL, you may have symptoms of low blood sugar even though your blood sugar is in the target range. But if you have had diabetes for many years, you may not have symptoms of low blood sugar until your blood sugar level is very low.
If your doctor thinks you have low blood sugar levels but you are not having symptoms, he or she may ask you to check your blood sugar more often. Your doctor may ask you to check your blood sugar in the middle of the night or to do a 3-day test using a continuous glucose monitor.
Check your symptoms to decide if and when you should see a doctor.
Health Tools help you make wise health decisions or take action to improve your health.
- Diabetes in Children: Preventing High Blood Sugar
- Diabetes in Children: Treating Low Blood Sugar
- Diabetes: Dealing With Low Blood Sugar From Insulin
- Diabetes: Dealing With Low Blood Sugar From Medicines
- Diabetes: Preventing High Blood Sugar Emergencies
- Gestational Diabetes: Dealing With Low Blood Sugar
Check Your Symptoms
The medical assessment of symptoms is based on the body parts you have.
- If you are transgender or nonbinary, choose the sex that matches the body parts (such as ovaries, testes, prostate, breasts, penis, or vagina) you now have in the area where you are having symptoms.
- If your symptoms aren’t related to those organs, you can choose the gender you identify with.
- If you have some organs of both sexes, you may need to go through this triage tool twice (once as "" and once as ""). This will make sure that the tool asks the right questions for you.
Symptoms of serious illness in a baby may include the following:
- The baby is limp and floppy like a rag doll.
- The baby doesn''t have one, seek care today.
- If it is evening, watch the symptoms and seek care in the morning.
- If the symptoms get worse, seek care sooner.
Call 911 Now
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Seek Care Now
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
- Call your doctor now to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don''s instructions on the use of insulin or diabetes medicines, diet, and exercise will help you avoid blood sugar problems. You will learn to recognize the symptoms and distinguish between high and low blood sugar levels. It may be hard for a parent of a young child to distinguish the difference between high and low blood sugar symptoms in a child.
When you have learned to recognize high or low blood sugar levels, you can take the appropriate steps to bring your blood sugar level back to your target blood sugar levels.
People who keep their blood sugar levels under control with diet, exercise, or oral diabetes medicines are less likely to have problems with high or low blood sugar levels. Do not drink alcohol if you have problems recognizing the early signs of low blood sugar.
Learn how to deal with high blood sugar levels
Be sure to know the steps for dealing with high blood sugar and how fast your insulin medicine will work to bring your blood sugar down. Some insulins work very fast while regular insulin takes a little longer to bring the sugar level down. Knowing how fast your insulin works will keep you from using too much too quickly.
Learn how to deal with low blood sugar levels
Because you have diabetes and can have low blood sugar levels, you need to keep some type of food with you at all times that can quickly raise your blood sugar level. These should be quick-sugar foods (about 15 grams of carbohydrate). Be sure to check your blood sugar level again 15 minutes after eating a quick-sugar (carbohydrate) food to make sure your level is getting back to your target range. If you continue to have low blood sugar, take another 15 grams of carbohydrate. When your blood sugar gets to 70 mg/dL or higher, you can eat your normal meals and snacks. Eat a small snack if your next meal or snack is more than a few hours away.
Foods to help raise blood sugar footnote 1, footnote 2, footnote 3
1 tablespoon (3 teaspoons)
Fruit juice or regular soda pop
½–¾ cup (4–6 ounces)
1 cup (8 ounces)
1 tablespoon (3 teaspoons)
Candy like Life Savers
Hard candy (like Jolly Rancher)
It is important to know that sugar foods like a candy bar or ice cream do not help raise low blood sugar levels quickly, because these foods also have fat and protein. So the body can''s blood sugar levels in two ways:
- It can increase hormones that may cause your blood sugar to go up.
- It can cause you to change the way you take care of yourself, a problem for all people with diabetes.
Stress can be both mental and physical. Some examples of stress include an illness, a bad day at work, and a tough problem at home. When you are under stress, your blood sugar levels change. For more information, see the topic Stress Management.
Blood sugar levels and exercise
You can keep your blood sugar levels under control when you exercise, so that you do not become too hungry or make your blood sugar level drop. There are two ways to keep your blood sugar levels under control:
- At the meal before your planned exercise, you can take less insulin, OR
- Before you exercise, eat some carbohydrate.
Keep a quick-sugar food with you during exercise in case your blood sugar level drops low.
Your doctor may recommend that you get vaccinations, such as a flu vaccine or pneumococcal vaccine, to prevent you from those illnesses.
Other places to get help
The American Diabetes Association has a lot of information on diabetes and can link you to support groups. For more information, call 1-800-DIABETES (1-800-342-2383) or see the organization''s high or low ( What is a PDF document? ) blood sugar problems to share with their child''t find what you're looking for?Dial 911 for emergencies