Hypoglycemia

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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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Hypoglycemia is the clinical syndrome that results from low blood sugar. The symptoms of hypoglycemia can vary from person to person, as can the severity. Classically, hypoglycemia is diagnosed by a low blood sugar with symptoms that resolve when the sugar level returns to the normal range. The medical term for blood sugar is blood glucose.

While people who do not have any metabolic problems can complain of symptoms suggestive of low blood sugar, true hypoglycemia usually occurs in people being treated for diabetes (type 1 and type 2). Individuals with pre-diabetes who have insulin resistance can also have low blood sugars on occasion if their high circulating insulin levels are further challenged by a prolonged period of fasting. There are other rare causes for hypoglycemia, such as insulin producing tumors (insulinomas) and certain medications. These uncommon causes of hypoglycemia will not be discussed in this article, which will primarily focus on the hypoglycemia occurring with diabetes mellitus and its treatment.

Despite our advances in the treatment of diabetes, hypoglycemic episodes are often the limiting factor in achieving optimal blood sugar control, because many medications that are effective in treating diabetes carry the risk of lowering the blood sugar level too much, causing symptoms of hypoglycemia. In large scale studies looking at tight control in both type 1 and type 2 diabetes, low blood sugars occurred more often in the patients who were managed most intensively. This is important for patients and physicians to recognize, especially as the goal for treating patients with diabetes become tighter blood sugar control.