Gangrene: The death of body tissues, usually due to a lack of blood supply, especially in the legs and feet.
Gastroparesis: A form of nerve damage that affects the stomach and intestines. With this condition, food is not digested properly and does not move through the stomach and intestinal tract normally. It can result in bouts of diarrhea or chronic constipation because the transit time of food can be altered by nerve damage. This type of nerve damage can also cause a significant problem with smooth control of blood sugars.
Gestational diabetes: A high blood sugar level that starts or is first recognized during pregnancy. As pregnancy progresses, there is an increased need for nutrients for the developing baby. Additionally, hormone changes during pregnancy affect the action of insulin, resulting in high blood sugar levels. Usually, blood sugar levels return to normal after childbirth. However, women who have had gestational diabetes are at increased risk of developing type 2 diabetes later in life. Gestational diabetes can increase complications during labor and delivery and increase the rates of fetal complications related to the increased size of the baby.
Glaucoma: An eye disease associated with increased pressure within the eye. Glaucoma can damage the optic nerve and cause impaired vision and blindness.
Glucagon: A hormone that raises the level of glucose in the blood by releasing stored glucose from the liver. Glucagon is sometimes injected when a person has lost consciousness (passed out) from a low blood sugar reaction. The injected glucagon helps raise the level of glucose in the blood.
Glucose: A simple sugar found in the blood. It is the body's main source of energy; also known as "dextrose."
Glucose Dehydrogenase (GDH) : An enzyme used for oxidation of glucose. A primary component of most blood glucose meters. When combined with other agents a biochemical reaction creates a measurable voltage. The measurment of the voltage, amperage or columb charge allows a meter to determine blood glucose levels.
FAD glucose dehydrogenase and potassium ferricyanide (FAD-GDH)
glucose dehydrogenase and pyrroloquinoline-quinone (GDH-PQQ) *
glucose dehydrogenase and nicotinamide adenine dinucleotide (GDH-NAD)
*In a safety alert published by the US Food and Drug Administration (FDA) in 2005 and amended 2010, people taking medications or using products containing these galactose, maltose and xylose are advised to take precautions as glucometers that use the glucose dehydrogenase pyrroloquinoline-quinone (GDH-PQQ) testing method may report highly elevated levels of glucose in the presence of these three sugars.
Glucose tolerance test: A test to determine if a person has diabetes. The test is done in a lab or doctor's office in the morning before the person has eaten. A period of at least 8 hours without any food is recommended prior to doing the test. First, a sample of blood is taken. Then the person drinks a liquid that has sugar in it. Two hours later, a second blood test is done. If the results of the fasting or first blood test are abnormal yet still not high enough to be considered in the diabetes range, then the person is said to have glucose intolerance. A fasting blood sugar greater than 126 mg/dl is considered diabetes. If the 2 hour blood test is abnormal but still not high enough to be considered in the diabetic range, this too, is considered an abnormal glucose tolerance. If the two hour test result shows a blood sugar greater than 200 mg/dl, the person is consider to have diabetes.
Glycated hemoglobin test (HbA1c): This is an important blood test to determine how well you are managing your diabetes. Hemoglobin is a substance in red blood cells that carries oxygen to tissues. It can also attach to sugar in the blood forming a substance called glycated hemoglobin or a Hemoglobin A1C. The test provides an average blood sugar measurement over a six to 12 week period and is used in conjunction with home glucose monitoring to make treatment adjustments. The ideal range for people with diabetes is generally less than 7%.