Hypoglycemia is a condition characterized by an abnormally low level of blood sugar (glucose), your body's main energy source.

Hypoglycemia is commonly associated with the treatment of diabetes. However, a variety of conditions, many of them rare, can cause low blood sugar in people without diabetes. Like fever, hypoglycemia isn't a disease itself — it's an indicator of a health problem.

Immediate treatment of hypoglycemia involves quick steps to get your blood sugar level back into a normal range — about 70 to 110 milligrams per deciliter, or mg/dL (3.9 to 6.1 millimoles per liter, or mmol/L) — either with high-sugar foods or medications. Long-term treatment requires identifying and treating the underlying cause of hypoglycemia.

Symptoms Causes Complications Prevention

Similar to the way a car needs gas to run, your body and brain need a constant supply of sugar (glucose) to function properly. If glucose levels become too low, as occurs with hypoglycemia, it can cause these signs and symptoms:

  • Heart palpitations
  • Fatigue
  • Pale skin
  • Shakiness
  • Anxiety
  • Sweating
  • Hunger
  • Irritability
  • Tingling sensation around the mouth
  • Crying out during sleep

As hypoglycemia worsens, signs and symptoms may include:

  • Confusion, abnormal behavior or both, such as the inability to complete routine tasks
  • Visual disturbances, such as blurred vision
  • Seizures
  • Loss of consciousness

People with severe hypoglycemia may appear as if they're intoxicated. They may slur their words and move clumsily.

Many conditions other than hypoglycemia may cause these signs and symptoms. A blood sample to test your blood sugar level at the time of these signs and symptoms is how to know for sure that hypoglycemia is the cause.

When to see a doctor

Seek a doctor's help immediately if:

  • You have what may be symptoms of hypoglycemia and you don't have diabetes.
  • You have diabetes and hypoglycemia isn't responding to treatment. Initial treatment of hypoglycemia is drinking juice or regular soft drinks, eating candy or taking glucose tablets. If this treatment doesn't raise your blood sugar and improve your symptoms, contact your doctor right away.

Seek emergency help if:

  • If someone with diabetes or a history of recurring hypoglycemia has symptoms of severe hypoglycemia or loses consciousness

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