Review Note

Hypoglycemia

• The lower limit of normal fasting plasma glucose is 70 mg/dL (3.9 mmol/L).

1. Iatrogenic Causes:
   • Excess insulin (e.g., insulin therapy)
   • Endogenous insulin excess (e.g., insulinoma)
2. Increased Insulin Sensitivity.
3. Chronic Alcohol Use, Fasting, or Exercise.
4. Drugs:
   • Beta blockers
   • Antidiabetics (e.g., sulfonylureas, meglitinides)
5. Hereditary and Acquired Conditions:
   • Liver or kidney failure
   • Malnutrition
   • Hypopituitarism or primary adrenal insufficiency

• Autonomic Symptoms:
  • Increased sympathetic activity: tremor, pallor, anxiety, tachycardia, sweating, palpitations
  • Increased parasympathetic activity: hunger, paresthesias, nausea, vomiting
• Neuroglycopenic Symptoms:
  • Agitation, confusion
  • Behavioral changes
  • Seizure, focal neurological signs
  • Somnolence → obtundation → stupor → hypoglycemic coma

• If the patient is conscious:
  • Administer oral glucose (15–20 g) or fast-acting carbohydrates such as glucose tablets, candy, or juice.
• If the patient is unconscious (or unable to ingest glucose):
  • In the hospital:
    • Administer 25 g of 50% glucose IV (dextrose) and monitor serum glucose levels.
    • Subsequent glucose infusions or food may be needed.
  • If both oral and IV routes are not feasible:
    • Administer 0.5–1.0 mg glucagon IM or SC.

• Patient education on insulin therapy.
• Monitoring blood sugar levels regularly.
• Careful use of medications like beta blockers.
• Keep a quick-acting sugar source handy.
• Drink alcohol responsibly and eat before drinking.
• Increase food intake when exercise levels increase.

• Life-threatening condition: Hypoglycemia can be fatal.
• Suspected severe hypoglycemia should be treated immediately, without waiting for blood glucose test results.
• Beta blockers can mask signs of hypoglycemia.
• Frequent hypoglycemic episodes in diabetics can lead to decreased awareness of symptoms.
• Patients may miss hypoglycemic warning signs due to autonomic neuropathy.
• Hypoglycemia is often seen after overdose or use of sulfonylureas and meglitinides, or when patients inject insulin and forget to eat.