What is High Blood Sugar?

High blood sugar or hyperglycemia is a condition in which there is a large amount of glucose in the blood. People are usually diagnosed with high blood sugar when they have more than 180 milligrams of glucose per deciliter of blood. This condition can lead to a number of complications, including death, which is why avoiding hyperglycemia is strongly recommended. Several conditions, most notably diabetes, predispose people to developing high levels of blood sugar.

To test for blood sugar levels, a sample of blood is taken and then analyzed. This can be done in a lab, or with a home test. Diabetics often use home fingersticking kits to monitor their blood sugar so that they can be alert to changes in their blood sugar. A blood glucose monitor for diabetes can be obtained from a medical supply company, and a doctor can provide instructions for its use.

There are two types of high blood sugar: fasting, and post-prandial. In fasting hyperglycemia, a test reveals high blood sugar levels many hours after eating, suggesting that the body is having trouble processing glucose. In post-prandial high blood sugar, the level of glucose in the blood is temporarily elevated after a meal. When a blood sugar test is performed, the patient will be asked about the last time he or she ate, as this information will be useful in interpreting the results.

In addition to appearing in diabetics, high blood sugar can also emerge as a surgical complication, a response to an eating disorder or infection, or simply as a result of eating an unusually large amount of food. High sugar consumption can also lead to high blood sugar. It is also possible to develop low blood sugar or hypoglycemia.

The signs of high blood sugar include dry mouth, thirst, frequent urination, hunger, fatigue, and blurred vision. If the condition is not treated, more serious complications including vision loss, damage to the internal organs, and an increased risk of serious infections may develop. People with high blood sugar are prone to yeast infections, and cuts and wounds will take longer to heal.

In extreme cases, high blood sugar can cause ketoacidosis in diabetics. In these instances, because the body lacks insulin to process glucose, all of the glucose ends up in the blood. In a search for energy, muscle mass begins to be used, causing a release of compounds known as ketones into the blood. Ketoacidosis is a very serious complication of diabetes, and it requires prompt medical attention.