Hypoglycemia: What It Is and How to Manage Sudden Low Blood Sugar

Hypoglycemia is a serious complication often seen in people with diabetes, especially those using insulin or sulfonylurea medications. If not promptly recognized and treated, hypoglycemia can lead to seizures, coma, and even death. Understanding its causes, symptoms, and first-aid response is crucial for both patients and caregivers.

What Is Hypoglycemia?

Hypoglycemia occurs when blood glucose drops below 3.9 mmol/L (70 mg/dL). Since glucose is the body’s primary energy source, low levels disrupt normal brain and body function, creating potentially life-threatening consequences.

Common Causes

• Insulin or oral medications: Incorrect dosage, delayed meals, or switching insulin types without medical guidance.
• Excessive exercise: More common in type 1 diabetes without adjusted insulin or food intake.
• Alcohol consumption: Alcohol inhibits glucose production in the liver and masks warning signs.
• Infections, pregnancy, or sudden weight loss: Can increase insulin sensitivity.

Risk Factors

• Inconsistent meals or poor understanding of diabetes management.
• Overly strict blood sugar control (very low HbA1c targets).
• Long-standing diabetes causing reduced warning signals.
• Previous episodes of severe hypoglycemia.
• Co-existing kidney or liver disease.

Signs and Symptoms

General

• Sudden fatigue, dizziness, headache.
• Sweating (especially on palms, forehead, underarms).
• Tremors, anxiety, rapid heartbeat.
• Blurred vision, confusion, or irritability.

Digestive

• Intense hunger, stomach pain, nausea.

Neurological

• Seizures, focal neurological deficits, or fainting.
• Severe cases may lead to hypoglycemic coma without warning.

Diagnosis

A blood glucose reading of <70 mg/dL (3.9 mmol/L) confirms hypoglycemia.
If suspected in emergencies, treatment should begin immediately without waiting for lab results.

Emergency Management

At Home (Mild to Moderate Hypoglycemia)

• Immediately consume 15 g of fast-acting carbohydrates (e.g., 3 sugar cubes, 1 glass of sweet juice, or candy).
• Recheck after 15 minutes; repeat if symptoms persist.
• Always carry glucose tablets or sugar when going out.

In Hospital (Severe Hypoglycemia)

• Stop diabetes medications temporarily.
• If patient is conscious: provide sweet food or drinks.
• If unconscious:
  • IV injection of 20–50 ml glucose 30%; may repeat if no improvement.
  • Continuous infusion of glucose 5–10% to maintain levels.
  • Glucagon 1 mg IM or SC if IV access is not immediately available.
• Monitor blood glucose every 4 hours.
• Manage complications such as cerebral edema if present.

Prevention Tips

• Eat meals on time and avoid skipping carbohydrates.
• Carry snacks or glucose when leaving home.
• Inform family, colleagues, and friends about your condition.
• Limit alcohol intake, especially on an empty stomach.
• Adjust insulin before exercise or during menstrual cycles (in women).
• Regularly check blood glucose, especially if unwell.
• Always carry a diabetes ID card and emergency contact information.