Which drug in the list is a calcium channel blocker used for hypertension?

• A. Amlodipine
• B. Gliclazide
• C. Ibuprofen
• D. Bisacodyl

Answer: (A)

Calcium channel blockers lower blood pressure by blocking L-type calcium channels in arterial smooth muscle, which reduces calcium entry, causes arterial dilation, and decreases systemic vascular resistance. Amlodipine is a dihydropyridine calcium channel blocker with strong vascular effects, making it a common choice for treating hypertension. It’s typically long-acting, supporting once-daily dosing, and its effect mainly reduces vascular resistance with relatively less impact on heart rate. The other drugs listed do not fit this mechanism or indication: gliclazide is a sulfonylurea antidiabetic used to increase insulin release, ibuprofen is an NSAID, and bisacodyl is a stimulant laxative.