Can hydroxychloroquine (HCQ) induce hypoglycemia in patients?

Hydroxychloroquine-Induced Hypoglycemia

Hydroxychloroquine can cause severe and potentially life-threatening hypoglycemia in patients with or without diabetes. 1 This adverse effect requires careful monitoring and patient education.

Mechanism and Risk

Hydroxychloroquine affects glucose metabolism through multiple mechanisms:

• Increases insulin sensitivity
• Increases insulin secretion
• Reduces hepatic insulin clearance
• Reduces systemic inflammation 2

Clinical Presentation

Hypoglycemia associated with hydroxychloroquine may present as:

• Fatigue, dizziness, headache
• Weakness and hunger
• Confusion
• Severe cases can progress to hypoglycemic coma 3, 4

Risk Factors

Several factors increase the risk of hydroxychloroquine-induced hypoglycemia:

• Concurrent diabetes treatment (insulin or sulfonylureas)
• Renal impairment
• Advanced age
• Malnutrition
• Comorbidities like sepsis or low albumin 5

Monitoring Recommendations

For patients starting hydroxychloroquine:

1. For diabetic patients on insulin or sulfonylureas:

   • Monitor blood glucose levels closely
   • Consider reducing insulin dose by approximately 30-37% 3
   • Be prepared to adjust antidiabetic medications

2. For non-diabetic patients:

   • Educate about signs and symptoms of hypoglycemia
   • Consider baseline glucose measurement
   • Instruct to report symptoms suggestive of hypoglycemia 4, 6

Management of Hypoglycemia

If hypoglycemia occurs:

1. Measure blood glucose in patients presenting with clinical symptoms suggestive of hypoglycemia
2. Adjust antidiabetic treatment as necessary
3. Consider discontinuation of hydroxychloroquine if severe or recurrent hypoglycemia occurs
4. Be aware that due to hydroxychloroquine's long half-life, hypoglycemic effects may take an extended time to resolve after discontinuation 1, 4

Clinical Pearls and Pitfalls

• Hypoglycemia can occur in patients with no history of diabetes 4, 6
• Effects may persist for weeks after discontinuation due to the drug's long half-life
• Symptoms may be mistaken for other conditions, especially in elderly patients who may have reduced awareness of hypoglycemic symptoms 5
• Hydroxychloroquine may interact with other QT-prolonging medications, potentially increasing cardiac risks 1

Special Populations

Elderly Patients

Elderly patients are particularly vulnerable to hypoglycemia and its adverse effects, including increased risk of falls, cognitive impairment, and increased mortality 5

Patients with Renal Impairment

Renal impairment can exacerbate hypoglycemia risk due to:

• Decreased renal gluconeogenesis
• Reduced clearance of insulin
• Impaired counterregulatory hormone responses 5

By understanding these risks and implementing appropriate monitoring strategies, clinicians can safely manage patients on hydroxychloroquine therapy while minimizing the risk of hypoglycemic events.