Hyperglycemia in diabetes can occur for many reasons. Know the causes, symptoms and treatments of high blood sugar and when to get emergency help.
High blood sugar, also called hyperglycemia, affects people who have diabetes. Several factors can play a role in hyperglycemia in people with diabetes. They include food and physical activity, illness, and medications not related to diabetes. Skipping doses or not taking enough insulin or other medication to lower blood sugar also can lead to hyperglycemia.
It's important to treat hyperglycemia. If it's not treated, hyperglycemia can become severe and cause serious health problems that require emergency care, including a diabetic coma. Hyperglycemia that lasts, even if it's not severe, can lead to health problems that affect the eyes, kidneys, nerves and heart.
Hyperglycemia usually doesn't cause symptoms until blood sugar (glucose) levels are high — above 180 to 200 milligrams per deciliter (mg/dL), or 10 to 11.1 millimoles per liter (mmol/L).
Symptoms of hyperglycemia develop slowly over several days or weeks. The longer blood sugar levels stay high, the more serious symptoms may become. But some people who've had type 2 diabetes for a long time may not show any symptoms despite high blood sugar levels.
Recognizing early symptoms of hyperglycemia can help identify and treat it right away. Watch for:
If hyperglycemia isn't treated, it can cause toxic acids, called ketones, to build up in the blood and urine. This condition is called ketoacidosis. Symptoms include:
During digestion, the body breaks down carbohydrates from foods — such as bread, rice and pasta — into sugar molecules. One of the sugar molecules is called glucose. It's one of the body's main energy sources. Glucose is absorbed and goes directly into your bloodstream after you eat, but it can't enter the cells of most of the body's tissues without the help of insulin. Insulin is a hormone made by the pancreas.
When the glucose level in the blood rises, the pancreas releases insulin. The insulin unlocks the cells so that glucose can enter. This provides the fuel the cells need to work properly. Extra glucose is stored in the liver and muscles.
This process lowers the amount of glucose in the bloodstream and prevents it from reaching dangerously high levels. As the blood sugar level returns to normal, so does the amount of insulin the pancreas makes.
Diabetes drastically reduces insulin's effects on the body. This may be because your pancreas is unable to produce insulin, as in type 1 diabetes. Or it may be because your body is resistant to the effects of insulin, or it doesn't make enough insulin to keep a normal glucose level, as in type 2 diabetes.
In people who have diabetes, glucose tends to build up in the bloodstream. This condition is called hyperglycemia. It may reach dangerously high levels if it is not treated properly. Insulin and other drugs are used to lower blood sugar levels.
Many factors can contribute to hyperglycemia, including:
Illness or stress can trigger hyperglycemia. That's because hormones your body makes to fight illness or stress can also cause blood sugar to rise. You may need to take extra diabetes medication to keep blood glucose in your target range during illness or stress.
Keeping blood sugar in a healthy range can help prevent many diabetes-related complications. Long-term complications of hyperglycemia that isn't treated include:
If blood sugar rises very high or if high blood sugar levels are not treated, it can lead to two serious conditions.
Diabetic ketoacidosis. This condition develops when you don't have enough insulin in your body. When this happens, glucose can't enter your cells for energy. Your blood sugar level rises, and your body begins to break down fat for energy.
When fat is broken down for energy in the body, it produces toxic acids called ketones. Ketones accumulate in the blood and eventually spill into the urine. If it isn't treated, diabetic ketoacidosis can lead to a diabetic coma that can be life-threatening.
Hyperosmolar hyperglycemic state. This condition occurs when the body makes insulin, but the insulin doesn't work properly. Blood glucose levels may become very high — greater than 600 mg/dL (33.3 mmol/L) without ketoacidosis. If you develop this condition, your body can't use either glucose or fat for energy.
Glucose then goes into the urine, causing increased urination. If it isn't treated, diabetic hyperosmolar hyperglycemic state can lead to life-threatening dehydration and coma. It's very important to get medical care for it right away.
To help keep your blood sugar within a healthy range:
Your health care provider sets your target blood sugar range. For many people who have diabetes, Mayo Clinic generally recommends the following target blood sugar levels before meals:
For many people who have diabetes, the American Diabetes Association generally recommends the following target blood sugar levels:
Your target blood sugar range may differ, especially if you're pregnant or you have other health problems that are caused by diabetes. Your target blood sugar range may change as you get older. Sometimes, reaching your target blood sugar range can be a challenge.
Routine blood sugar monitoring with a blood glucose meter is the best way to be sure that your treatment plan is keeping your blood sugar within your target range. Check your blood sugar as often as your health care provider recommends.
If you have any symptoms of severe hyperglycemia — even if they seem minor — check your blood sugar level right away.
If your blood sugar level is 240 mg/dL (13.3 mmol/L) or above, use an over-the-counter urine ketones test kit. If the urine test is positive, your body may have started making the changes that can lead to diabetic ketoacidosis. Talk to your health care provider about how to lower your blood sugar level safely.
During an appointment, your health care provider may conduct an A1C test. This blood test shows your average blood sugar level for the past 2 to 3 months. It works by measuring the percentage of blood sugar attached to the oxygen-carrying protein in red blood cells, called hemoglobin.
An A1C level of 7% or less means that your treatment plan is working and that your blood sugar was consistently within a healthy range. If your A1C level is higher than 7%, your blood sugar, on average, was above a healthy range. In this case, your health care provider may recommend a change in your diabetes treatment plan.
For some people, especially older adults and those with certain medical conditions, a higher A1C level of 8% or more may be appropriate.
How often you need the A1C test depends on the type of diabetes you have and how well you're managing your blood sugar. Most people with diabetes receive this test 2 to 4 times a year.
Talk to your health care provider about managing your blood sugar. Understand how different treatments can help keep your glucose levels within your target range. Your health care provider may suggest the following:
If you have signs and symptoms of diabetic ketoacidosis or hyperosmolar hyperglycemic state, you may be treated in the emergency room or admitted to the hospital. (4p4) Emergency treatment can lower your blood sugar to a normal range. Treatment usually includes:
As your body returns to normal, your health care provider will consider what may have triggered the severe hyperglycemia. Depending on the circumstances, you may need additional tests and treatment.
If you have trouble keeping your blood sugar within your target range, schedule an appointment to see your health care provider. Your provider can help you make changes to better manage your diabetes.
Here's information to help you get ready for your appointment and know what to expect from your health care provider.
For hyperglycemia, questions you may want to ask include:
Illness or infections can cause your blood sugar to rise, so it's important to plan for these situations. Talk to your health care provider about creating a sick-day plan. Questions to ask include: