DefinitionBy Mayo Clinic staff
Low blood sugar (hypoglycemia) can affect people who have diabetes. It occurs when there's too much insulin and not enough sugar (glucose) in your blood. Hypoglycemia is defined as blood sugar below 70 milligrams per deciliter (mg/dL) or 4 millimoles per liter (mmol/L). Several factors can cause hypoglycemia in people with diabetes, including taking too much insulin or other diabetes medications, skipping a meal, or exercising harder than usual.
Pay attention to early warning signs, so you can treat low blood sugar promptly. Treatment involves short-term steps — such as taking glucose tablets — to raise your blood sugar into a normal range.
Left untreated, diabetic hypoglycemia can lead to seizures and loss of consciousness. This is considered a medical emergency. Tell family and friends what symptoms to look for and what to do in case you're not able to treat diabetic hypoglycemia yourself.
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