Discusses high and low blood sugar levels caused by diabetes. Suggests when to check blood sugar levels. Covers symptoms. Offers home treatment and prevention tips. Includes info on diabetes emergencies.
Diabetes-Related High and Low Blood Sugar Levels
Diabetes-related blood sugar levels
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.
You can help avoid blood sugar problems 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' help to keep their blood sugar levels in a target
range and to exercise safely. Be sure that children learn the
symptoms of both
low blood sugar so they can tell others when they need help. There are many
support groups and diabetes education centers to help parents and children
understand about blood sugar, exercise, diet, and medicines.
especially may have a hard time keeping their blood sugar levels in control
because their bodies are growing and developing. Also, they want to be with
their friends and eat foods that may affect their blood sugar. Having diabetes
during the teenage years is not easy. But your teen is at an excellent age to
understand the disease and its treatment and to take over some of the
responsibilities of his or her care.
If your blood sugar level
reads too high or too low but you are feeling well, you may want to recheck
your sugar level or recalibrate your blood glucose meter. The problem may be
with either your blood sample or the machine.
High blood sugar (hyperglycemia)
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.
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
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)
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
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
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 normal 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.
If you are answering for someone else: Is the person unconscious now?
(If you are answering this question for yourself, say no.)
Are you back to your normal level of alertness?
After passing out, it's normal to feel a little confused, weak, or lightheaded when you first wake up or come to. But unless something else is wrong, these symptoms should pass pretty quickly and you should soon feel about as awake and alert as you normally do.
Has returned to normal after loss of consciousness
Has returned to normal after loss of consciousness
Did the loss of consciousness occur during the past 24 hours?
Here is what you can do to treat low blood sugar. If at any point during these steps you think you are getting
worse, seek care immediately.
Eat some quick-sugar food, such as a tablespoon of
sugar, 0.5 cup (120 mL) of
fruit juice or soda pop,
8 fl oz (240 mL) of fat-free
milk, several pieces of hard candy, or 3 glucose tablets.
about 15 minutes. Then check your blood sugar.
If your blood sugar is above 70 and your
symptoms have improved, you can go back to your regular schedule of meals and
If your blood sugar is still low, eat another quick-sugar
food, wait 15 minutes, and check your blood sugar again. If your blood sugar is
still below 70, you may need medical care soon.
Symptoms of diabetic ketoacidosis may
Flushed, hot, dry skin.
Drowsiness or difficulty waking up.
Fruity breath odor.
Belly pain, loss of
appetite, and vomiting.
Symptoms of serious illness may
A severe headache.
Mental changes, such as feeling confused or much less
Extreme fatigue (to the point where it's hard for you to
Symptoms of infection may
Increased pain, swelling, warmth, or redness in or
around the area.
Red streaks leading from the area.
Pus draining from the area.
You can test urine for ketones at home using special tablets or test strips. Ketones are
substances made by the body when it burns fat instead of sugar. They are a sign
that your blood sugar is out of control.
To do the test:
Collect a urine sample in a clean container.
Follow the directions on the test.
If either the test
strip or the urine changes color when the tablet is dropped into the sample,
the urine sample contains ketones.
Test results may range from negative to 4+, from small to large, or
from low to high. (For tests that read from negative to 4+, more than 1+ means
that you have a moderate to large amount of ketones in your urine.)
Early symptoms of low blood sugar may
Feeling nervous, shaky, and
Extreme hunger and slight nausea.
If blood sugar continues to drop, you may start to have more
Try Home Treatment
You have answered all the questions. Based on your answers, you may be
able to take care of this problem at home.
Try home treatment to relieve the
Call your doctor if symptoms get worse or you have any
concerns (for example, if symptoms are not getting better as you would expect).
You may need care sooner.
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
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
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
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. When your blood sugar gets to 70 mg/dL or higher, you can eat your normal meals and snacks.
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't use the sugar
(carbohydrate) in these foods quickly to raise the blood sugar level.
Since low blood sugar levels can quickly become a medical
emergency, be sure to wear medical identification, such as a
medical alert bracelet, to let people know you have diabetes so they can get
help for you.
If you have severe symptoms of low blood sugar,
someone else may need to give you a
shot of glucagon. If this occurs, be sure to call your doctor immediately to let
him or her know this has happened.
Although high blood sugar (hyperglycemia)
and low blood sugar (hypoglycemia) have very different symptoms and treatments,
they are both caused by blood sugar and insulin imbalances. The steps you take
to control your blood sugar level will help prevent both high and low blood
Be sure to have identification that says you have diabetes, such as a
medical alert bracelet, with you at all times. This
will help other people take steps to care for you if you are not able tell them
about your medical condition.
You can take steps to prevent high
and low blood sugar emergencies.
Follow your treatment plan.
your blood sugar levels regularly to detect early
changes before an emergency develops. Treat your symptoms of high or low blood
sugar quickly to prevent more problems.
Control your stress to prevent your blood sugar level from increasing slowly over several days.
how much alcohol you drink. Do not drink alcohol if you have problems recognizing the early signs of low blood sugar.
home blood sugar tests to determine whether your blood
sugar is in your
target range. Work with your doctor to set your
individual treatment goals. If you can consistently maintain this level of
control, you will have very few blood sugar level emergencies.
No matter how skilled you are at
monitoring and controlling your blood sugar levels, you are still at risk for
high or low blood sugar levels that are brought on by stressful situations.
Stress can affect your body's blood sugar levels in two ways:
It can cause you to
change the way you take care of yourself, a problem for all people with
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
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
exercise, eat some carbohydrate.
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(What is a PDF document?) vaccine
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 website: www.diabetes.org/home.
Be sure to take your daily blood sugar (glucose) monitoring
logbook to your appointment. If you have specific records of your high(What is a PDF document?) and low(What is a PDF document?) blood sugar
problems, be sure to take those records.
Parents will also need to keep records of their child's high or low(What is a PDF document?) blood sugar problems to share with their child's doctor.
How this information was developed to help you make better health decisions.