Health Information and Tools > Patient Care Handouts >  Learning About High Blood Sugar

Main Content

Learning About High Blood Sugar

What is high blood sugar?

Your body turns the food you eat into glucose (sugar), which it uses for energy. But if your body isn't able to use the sugar right away, it can build up in your blood and lead to high blood sugar.

When the amount of sugar in your blood stays too high for too much of the time, you may have diabetes. Diabetes is a disease that can cause serious health problems.

The good news is that lifestyle changes may help you get your blood sugar back to normal and avoid or delay diabetes.

What causes high blood sugar?

Sugar (glucose) can build up in your blood if you:

  • Have insulin resistance.
  • Don't take enough insulin or miss a dose of your diabetes medicine.
  • Take certain medicines, such as steroids.

What are the symptoms?

Having high blood sugar may not cause any symptoms at all. Or it may make you feel very thirsty or very hungry. You may also urinate more often than usual, have blurry vision, or lose weight without trying.

How is high blood sugar treated?

You can take steps to lower your blood sugar level if you understand what makes it get higher. Your doctor may want you to learn how to test your blood sugar level at home. Then you can see how illness, stress, or different kinds of food or medicine raise or lower your blood sugar level.

Other tests may be needed to see if you have diabetes.

How can you prevent high blood sugar?

  • Watch your weight. If you're overweight, losing just a small amount of weight may help. Reducing fat around your waist is most important.
  • Limit the amount of calories, sweets, and unhealthy fat you eat. Ask your doctor if a dietitian can help you. A registered dietitian can help you create meal plans that fit your lifestyle.
  • Get at least 2½ hours of exercise a week. Exercise helps control your blood sugar. It also helps you maintain a healthy weight. Walking is a good choice. You also may want to do other activities, such as running, swimming, cycling, or playing tennis or team sports. If your doctor says it's okay, do muscle-strengthening exercises at least 2 times a week.
  • If your doctor prescribed medicines, take them exactly as prescribed. Call your doctor or nurse advice line if you think you are having a problem with your medicine. You will get more details on the specific medicines your doctor prescribes.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Where can you learn more?

Go to

Enter O108 in the search box to learn more about "Learning About High Blood Sugar".

Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.