What are the causes and treatments of hypoglycemia (low blood sugar)?

Causes and Treatment of Hypoglycemia (Low Blood Sugar)

Hypoglycemia (blood glucose ≤70 mg/dL) requires prompt treatment with 15-20g of glucose, with blood glucose rechecked after 15 minutes and treatment repeated if hypoglycemia persists. 1, 2

Causes of Hypoglycemia

Medication-Related Causes

• Insulin excess is the most common cause of hypoglycemia, particularly in people with type 1 diabetes and advanced type 2 diabetes 3, 4
• Insulin secretagogues (e.g., sulfonylureas) can also cause hypoglycemia 1
• Drug interactions that increase insulin sensitivity or lower blood glucose (e.g., salicylates, sulfa antibiotics, certain antidepressants, kidney and blood pressure medications) 3
• Medication timing errors or dosing errors (taking too much insulin) 3

Behavioral and Lifestyle Factors

• Missing or delaying meals 3
• Exercising or working more than usual without adjusting medication or food intake 3
• Alcohol consumption (inhibits gluconeogenesis) 5, 3
• Prolonged fasting 6
• Post-bariatric surgery (altered gut hormone response) 5

Pathophysiological Causes

• Defective glucose counterregulation (failure of decreasing insulin and failure of compensatory increasing counterregulatory hormones) 7, 4
• Diseases of the adrenal, pituitary, or thyroid gland 3
• Progression of kidney or liver disease 3
• Insulinoma (insulin-producing tumor) 8
• Autoimmune hypoglycemia syndrome 8
• Non-islet cell tumors 8
• Critical illness 7

Treatment of Hypoglycemia

Immediate Treatment for Conscious Patients

• For blood glucose ≤70 mg/dL, administer 15-20g of glucose orally 1, 2
• Pure glucose is preferred as it produces a greater rise in plasma glucose than other carbohydrates 1, 2
• For patients using automated insulin delivery systems, a lower dose of 5-10g carbohydrates may be appropriate (except with exercise-induced hypoglycemia) 1, 5
• Recheck blood glucose after 15 minutes; if hypoglycemia persists, repeat treatment 1, 2
• After blood glucose normalizes, consume a meal or snack containing complex carbohydrates and protein to prevent recurrence 5

Treatment for Severe Hypoglycemia (Unconscious Patient)

• For patients unable to consume carbohydrates orally, glucagon is indicated 1, 2
• All individuals treated with insulin or at high risk of hypoglycemia should be prescribed glucagon 1
• Family members, roommates, school personnel, or caregivers should be instructed on glucagon administration 1
• In medical settings, intravenous glucose may be administered 3

Special Populations

• Young children with type 1 diabetes and elderly individuals are particularly vulnerable to hypoglycemia due to reduced ability to recognize symptoms 1
• Patients with comorbidities (chronic renal failure, hepatic dysfunction, cognitive dysfunction) are at higher risk 7
• Individualized glycemic goals, patient education, and bedtime snacks may be needed for these populations 1

Prevention Strategies

Medication Management

• Adjust insulin or medication doses based on patterns of hypoglycemia 3
• Consider medication timing in relation to meals and exercise 3
• Be aware of drug interactions that may increase hypoglycemia risk 3

Dietary Approaches

• Avoid prolonged fasting periods 6
• Implement consistent meal timing when on fixed insulin regimens 1
• Include protein and/or fat with meals to slow carbohydrate absorption 5
• For those at high risk, consider small, frequent meals containing complex carbohydrates 5

Monitoring and Education

• Teach recognition of hypoglycemia symptoms (sweating, pallor, palpitations, tremors, headache, behavioral changes) 5, 3
• Instruct patients to always carry a source of fast-acting carbohydrates 5
• For those with recurrent hypoglycemia, consider continuous glucose monitoring 6
• For hypoglycemia unawareness, a 2-3 week period of scrupulous avoidance of hypoglycemia is recommended 4

Common Pitfalls in Hypoglycemia Management

• Treating with foods high in protein without adequate glucose content (protein may increase insulin secretion) 1, 2
• Failing to recheck blood glucose after initial treatment 2
• Not carrying fast-acting glucose sources for emergency treatment 5
• Overlooking hypoglycemia in patients who present with unusual behaviors or neurological symptoms 7
• Not adjusting insulin doses before planned exercise or during illness 3
• Targeting overly tight glucose control in vulnerable populations 9

By understanding the causes of hypoglycemia and implementing appropriate treatment and prevention strategies, patients can reduce their risk of serious hypoglycemic episodes and maintain better overall glycemic control.