A patient on long-term hydrochlorothiazide for hypertension develops new-onset hyperglycemia. The mechanism by which thiazides impair glucose tolerance includes:
- A Direct destruction of pancreatic beta cells
- B Hypokalemia impairing insulin secretion and peripheral insulin resistance ✓
- C Increased hepatic gluconeogenesis due to drug-induced hepatitis
- D Enhanced gastrointestinal glucose absorption
Correct answer: B. Hypokalemia impairing insulin secretion and peripheral insulin resistance
Explanation
Thiazide-induced hypokalemia impairs insulin secretion from pancreatic beta cells and causes peripheral insulin resistance, leading to glucose intolerance or overt diabetes. Potassium supplementation can partially reverse this effect. Thiazides do not directly destroy beta cells or cause hepatitis.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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