This study aimed to investigate how the binding of gliclazide may be affected by the presence of other drugs in the system, especially those commonly used in the treatment of hypertension in diabetic patients: (a) quinapril hydrochloride (QUI), an ACE inhibitor; (b) valsartan (VAL), a selective antagonist of angiotensin receptor 1; (c) furosemide (FUR), a loop diuretic; (d) amlodipine besylate (AML), a calcium channel blocker; and (e) atenolol (ATN), a cardioselective beta-adrenolytic agent. This evidence concerns the gene ACE and hypertensive disorder.