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Cook Children's

Cook Children's

801 Seventh Avenue
Fort Worth, TX 76104

682-885-4000


When Blood Sugar Is Too High

If you have diabetes, you know that controlling blood sugar levels (or blood glucose levels) is important. You have to keep your levels steady. Having a blood sugar level that's too high can make you feel lousy, and having it often can be unhealthy.

What Is High Blood Sugar?

The is the amount of glucose in the blood. Glucose is a sugar that comes from the foods we eat, and it's also formed and stored inside the body. It's the main source of energy for the cells of our body, and it's carried to each cell through the bloodstream.

Hyperglycemia (pronounced: hi-per-gly-SEE-me-uh) is the medical word for high blood sugar levels. High blood sugar levels happen when the body either can't make insulin (type 1 diabetes) or can't respond to insulin properly (type 2 diabetes). The body needs insulin so glucose in the blood can enter the cells of the body where it can be used for energy. In people who have developed diabetes, glucose builds up in the blood, resulting in hyperglycemia.

Having too much sugar in the blood for long periods of time can cause serious health problems if it's not treated. Hyperglycemia can damage the vessels that supply blood to vital organs, which can increase the risk of heart disease and stroke, kidney disease, vision problems, and nerve problems. These problems don't usually show up in kids or teens who have had the disease for only a few years. But they can happen in adulthood in some people with diabetes, particularly if they haven't managed or controlled their diabetes well.

Blood sugar levels are considered high when they're above your target range. Your diabetes health care team will let you know what your target blood sugar levels are.

What Causes High Blood Sugar Levels?

Managing diabetes is like a three-way balancing act because you have to watch:

  1. the medicines you take (or pills)
  2. the food that you eat
  3. the amount of exercise you get

All three need to be balanced. If any one of these is off, blood sugar levels can be too. In general, higher than normal blood glucose levels can be caused by:

  • not taking your diabetes medicine when you're supposed to or not taking the right amounts
  • not following the meal plan (like eating too much on a special occasion without adjusting your diabetes medicines)
  • not getting enough exercise
  • having an illness, like the flu
  • stress
  • taking other kinds of medicines that affect how your diabetes medicines work

A single high blood sugar reading usually isn't cause for alarm — it happens to everyone with diabetes from time to time. But if you have high blood sugar levels a lot, let your parents and your diabetes health care team know. Insulin or meal plans may need adjusting, or you may have an equipment issue, like an insulin pump that isn't working right. Whatever the case, make sure you get help so you can get your blood sugar levels back under control.

What Are the Signs & Symptoms of High Blood Sugar Levels?

Signs of high blood sugar levels include:

  • Peeing a lot: The kidneys respond by flushing out the extra glucose in urine. People with high blood sugar need to pee more often and in larger amounts.
  • Drinking a lot: Someone losing so much fluid from peeing that often can get very thirsty.
  • Losing weight even though your appetite has stayed the same: If there isn't enough insulin to help the body use glucose, the body breaks down muscle and stored fat instead in an attempt to provide fuel to hungry cells.
  • Feeling tired: Because the body can't use glucose for energy properly, a person may feel unusually tired.

How Are High Blood Sugar Levels Treated?

Treating high blood sugar levels involves fixing what caused them in the first place. Your diabetes health care team will give you specific advice on how to keep your blood sugar levels in a healthy range. But here are some ways to manage the common causes of high blood sugar levels:

Reason for High Blood Sugar LevelWhat to Do
Not getting enough insulin or other diabetes medicine
  • Make sure that you take the proper type of insulin and the correct dose at the right time.
  • Check that insulin is not expired.
  • Make sure that all equipment (pumps, meters, etc.) is working properly.
  • Diabetes medicines may need to be changed or adjusted — check with your diabetes health care team.
Not following the meal plan (like eating too much food on special occasions without adjusting medicines)
  • Work with a registered dietitian to make adjustments to your meal plan as needed.
  • Adjust insulin/pills when you eat more or less than recommended on your meal plan (your diabetes health care team can instruct you on making adjustments).
Not getting enough exercise
  • Figure out a plan to make time for exercise.
  • Adjust your medicines based on the diabetes health care team's instructions.
Illness or stress
  • Contact your diabetes health care team.
  • Continue to take insulin (the dose may need to be adjusted).
  • Check your blood sugar levels frequently.
Use of other medicines that can increase blood sugar
  • Contact your diabetes health care team if you start taking any other medicine.
  • Your insulin or pills may need to be adjusted while you take the medicine that's causing high blood sugar levels.

Don't worry too much if you get a high blood sugar reading occasionally. But if you have consistently high blood sugar levels, you should talk to your doctor about it.

What Is Diabetic Ketoacidosis (DKA)?

When the body doesn't have enough insulin, glucose stays in the blood and can't get into the body's cells to be used for energy. This can happen, for example, when someone skips doses of insulin or when the need for insulin suddenly increases (like when a person is sick with the flu) and the doses are not adjusted.

When the body can't use glucose for fuel, it starts to use fat. When this happens, chemicals called ketones are released into the blood. Some of these ketones, like extra glucose, pass out of the body through the urine.

High levels of ketones in the blood can be a problem because they cause the blood to become acidic. Too much acid in the blood throws off the body's chemical balance and causes the symptoms listed below. In people with diabetes, this problem is called diabetic (pronounced: kee-toe-as-ih-DOE-siss), or DKA. DKA is a very serious condition that can lead to coma or death if it's not treated. The good news, though, is that it's preventable and can be treated.

DKA happens more often in people with type 1 diabetes, but can sometimes also happen to those with type 2 diabetes.

What Are the Signs & Symptoms of DKA?

The symptoms of diabetic ketoacidosis usually don't develop all at once — they usually come on slowly over several hours. People who have DKA may:

  • feel really tired
  • feel really thirsty or pee way more than usual
  • have a dry mouth and signs of dehydration

These symptoms are caused by the high blood sugar levels that usually happen before someone develops DKA. If the person doesn't get treatment, these signs of DKA can happen:

  • abdominal pain
  • nausea and/or vomiting
  • fruity breath odor
  • rapid, deep breathing
  • confusion
  • unconsciousness ("diabetic coma")

Checking for DKA

How do you know if you have DKA? Because the signs and symptoms of DKA can seem like the flu, it's important to check blood sugar levels and urine (or blood) ketones when you're sick or if you think you're having symptoms of DKA.

Because high levels of ketones appear in the urine (as well as the blood), ketones can be checked at home by testing a sample of your pee. If the urine test for ketones is negative, it usually means your symptoms are not due to DKA.

Follow your diabetes management plan about when to check for ketones and what to do if the test is positive. In some cases, your diabetes management team may also have you use special blood test strips to check ketone levels in your blood too.

How Is DKA Treated?

DKA is very serious, but it can be treated if you go to the doctor or hospital right away. To feel better, a person with DKA needs to get insulin and fluids through a tube that goes into a vein in the body (an IV).

Let your parents or someone on your diabetes health care team know if you have any of these symptoms or are sick and don't know what to do to take care of your diabetes.

Always wear a medical identification bracelet or necklace that says you have diabetes. Then, if you are not feeling well, whoever's helping you will know to call for medical help. Medical identification can also include your doctor's phone number or a parent's phone number.

Avoiding High Blood Sugar and DKA

No matter how well they take care of themselves, people with diabetes will sometimes have high blood sugar levels. But the best way to avoid problems is to keep your blood sugar levels as close to your desired range as possible, which means following your diabetes management plan. Checking your blood sugar levels several times a day will let you know when your blood sugar level is high. Then you can treat it and help prevent DKA from happening.

High blood sugar levels don't always cause symptoms, and a person who isn't testing regularly might be having blood sugar levels high enough to damage the body without even realizing it. Doctors may use the HbA1c test to find out if someone has been having high blood sugar levels over time, even if the person has not had obvious symptoms.

Here are some other tips for avoiding high blood sugar levels and preventing DKA:

  • Try to eat all your meals and snacks on time and not skip any.
  • Take the right amount of insulin.
  • Check your blood sugar levels regularly and your ketone levels when your diabetes management plan recommends it.
  • Stick to your diabetes management plan.
Medically reviewed by: Steven Dowshen, MD
Date reviewed: May 2018