What Are the First Signs and Symptoms of Hypoglycemia?

Medically Reviewed on 7/23/2025

What is hypoglycemia?

Signs and Symptoms of Hypoglycemia
Worsening of hypoglycemia results in blurred vision, confusion, loss of consciousness, seizures, coma, and death.

Hypoglycemia is an abnormally low blood sugar level. If the blood sugar drops to extremely low levels, it becomes an emergency condition that can even lead to coma or death.

Hypoglycemia is most common in patients with diabetes mellitus who are taking insulin and skip their meals. Overdosing of insulin can also cause hypoglycemia.

There are two types of hypoglycemia:

  • Reactive hypoglycemia: This usually occurs after having a meal.
  • Fasting hypoglycemia: Often associated with medications or disease. Enzyme deficiencies are the main underlying cause of fasting hypoglycemia.

Patients with hypoglycemia should learn to recognize early signs and symptoms to avoid serious complications.

What are the signs and symptoms of hypoglycemia?

The following hypoglycemia symptoms occur when blood sugar goes below 70 milligrams per deciliter (mg/dL):

  • Giddiness
  • Sweating
  • Pale skin
  • Cold and moist skin
  • Fast/irregular heartbeat
  • Shivering
  • Difficulty in speaking
  • Anxiety
  • Sleepiness
  • Crankiness

Worsening of hypoglycemia results in:

What causes hypoglycemia?

Causes of hypoglycemia include:

  • Diabetes medication overdose (oral medicines or insulin)
  • Fasting for prolonged period
  • Infection
  • Diet changes
  • Changes in metabolism
  • Liver disease
  • Tumor of the pancreas
  • Abnormalities in a hormone-secreting gland
  • Post weight-loss surgery
  • Drugs such as ethanol, haloperidol, pentamidine, quinine
  • Deficiency of hormones
  • Serious illness of heart, liver and kidney
  • Pregnancy
  • Growth hormone insufficiency
  • Rare enzyme defects
  • Unknown causes

SLIDESHOW

Diabetes: What Raises and Lowers Your Blood Sugar Level? See Slideshow

How is hypoglycemia treated?

Hypoglycemia is primarily treated with medications.

The main medications used in the treatment of hypoglycemia include:

  • Glucose supplements: Dextrose
  • Glucose-elevating agents: Glucagon
  • Inhibitors of insulin hormone secretion: Diazoxide
  • Anticancer agents: Streptozocin

Other therapies hypoglycemia include:

  • Fasting hypoglycemia:
    • Dietary changes such as frequent snacking
    • Intravenous glucose infusion
    • Intravenous octreotide
  • Reactive hypoglycemia:
    • Dietary changes such as restriction of refined carbohydrates and avoidance of sugar
    • Alpha-glucosidase inhibitors such as acarbose

Surgical treatment might be necessary for any tumor of the pancreas.

How serious is hypoglycemia?

Severe hypoglycemia can be life-threatening and fatal. Patients with reactive hypoglycemia have a better chance of improvement with dietary changes.

Hypoglycemia, if severe, can lead to:

  • Coma
  • Heart problems
  • Impaired memory
  • Diminished language skills
  • Impaired coordination

Other recommendations are:

  • Do not skip meals, especially if you have diabetes and are taking medications.
  • Exercise for at least 30 minutes to one hour after meals.
  • Monitor blood sugar levels routinely.
  • Avoid excessive dosing of medications.
  • Drink alcohol moderately.
  • Include a balanced diet in your routine.
  • Avoid consumption of sugar.
  • Avoid driving if you have hypoglycemia.

Patients with hypoglycemia should learn to recognize early symptoms to avoid serious complications.

Medically Reviewed on 7/23/2025
References
Medscape Medical Reference