High Blood Sugar
High Blood Sugar (Hyperglycemia) Overview
Whenever the glucose (sugar) level in one's blood rises high temporarily, this condition is known as hyperglycemia. The opposite condition, low blood sugar, is called hypoglycemia.
Glucose comes from most foods, and the body uses other chemicals to create glucose in the liver and muscles. The blood carries glucose (blood sugar) to all the cells in the body. To carry glucose into the cells as an energy supply, cells need help from insulin. Insulin is a hormone made by the pancreas, an organ near the stomach.
The pancreas releases insulin into the blood, based upon the blood sugar level. Insulin helps move glucose from digested food enter into cells. Sometimes, the body stops making insulin (as in type 1 diabetes), or the insulin does not work properly (as in type 2 diabetes). In diabetic patients, glucose does not enter the cells sufficiently, thus staying in the blood and creating high blood sugar levels.
Blood sugar levels can be measured in seconds by using a blood glucose meter, also known as a glucometer. A tiny drop of blood from the finger or forearm is placed on a test strip and inserted into the glucometer. The blood sugar (or glucose) level is displayed digitally within seconds.
Blood glucose levels vary widely throughout the day and night in people with diabetes. Ideally, blood glucose levels range from 90 to 130 mg/dL before meals, and below 180 mg/dL within 1 to 2 hours after a meal. Adolescents and adults with diabetes strive to keep their blood sugar levels within a controlled range, usually 80-150 mg/dL before meals. Doctors and diabetes health educators guide each patient to determine their optimal range of blood glucose control.
When blood sugar levels remain high for several hours, dehydration and more serious complications can develop. Moreover, even mild hyperglycemia (a fasting blood sugar over 109 mg/dL in adolescents/adults or over 100 mg/dL in children before puberty) - when unrecognized or inadequately treated for several years - can damage multiple tissues in the brain, kidneys, and arteries. When hyperglycemia is associated with the presence of ketones in the urine, this state demands immediate medical attention. When blood sugar levels rise and stay high (over 165 mg/dL consistently) for days to weeks, diabetes should be suspected and must be treated.
High blood sugar level fluctations occur daily in people with diabetes. It is important to control blood sugar levels through diet, exercise, and medication (if prescribed), to know the symptoms of elevated blood sugar, and to seek treatment, when necessary.
Medically Reviewed by a Doctor on 5/2/2014
Must Read Articles Related to High Blood Sugar (Hyperglycemia)
Diabetic Eye Disease
Diabetic eye disease is a complication from diabetes. Types of diabetic eye disease include background diabetic retinopathy, nonproliferative diabetic retinopat...learn more >>
Diabetic Foot Care
Read about diabetic foot care. Causes of foot problems in people with diabetes include footwear, nerve damage, poor circulation, trauma, infections, and smoking...learn more >>
Diabetic ketoacidosis (DKA) occurs when a person with diabetes becomes dehydrated. Causes of diabetic ketoacidosis include infection, missed insulin, or newly d...learn more >>
Patient Comments & Reviews
The eMedicineHealth doctors ask about High Blood Sugar (Hyperglycemia):