Glucose is a type of sugar. It is your body's main source of energy. Hypoglycemia is a condition where the level of glucose in your blood becomes low enough to cause symptoms. For most people, this level is 50-60 mg/dl (milligrams per deciliter), though anything below 70 mg/dl is considered below normal. When blood glucose drops too low, your body does not have enough energy to function properly.

Glucose in Blood
glucose and RBC
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Medication for diabetes is the most common cause particularly when combined with the following factors:

  • Taking too much blood sugar-lowering medication
  • Delaying or missing meals, or eating too little at meals
  • Too much or too strenuous exercise

Reactive hypoglycemia may also occur in people without diabetes. It is now thought to be quite rare.

Other causes of hypoglycemia include:

  • Drinking too much alcohol (especially binge drinking coupled with not eating)
  • Prolonged fasting
  • Early pregnancy
  • Long periods of strenuous exercise
  • Certain medications may increase the risk of hypoglycemia (people on beta blockers who exercise, aspirin in children)
  • Certain pituitary or adrenal gland conditions
  • Certain liver conditions
  • Certain types of stomach surgery
  • Certain autoimmune conditions
  • Hereditary enzyme or hormone deficiencies
  • A reaction to certain foods (rarely, eating unripe ackee fruit from Jamaica)
  • Pancreatic tumors
  • Tumors that produce an insulin-like hormone
  • Any severe or protracted illness, such as: