Nifedipine is a dihydropyridine calcium channel blocker used primarily for hypertension and angina pectoris. It works by inhibiting L-type voltage-gated calcium channels in vascular smooth muscle and cardiac muscle cells, reducing calcium influx. This leads to vasodilation, notably of peripheral arteries and coronary arteries, which decreases peripheral vascular resistance and myocardial oxygen demand while increasing oxygen supply to the heart.

Pharmacologically, nifedipine lowers blood pressure by decreasing systemic vascular resistance (afterload) and dilates coronary vessels, relieving angina symptoms. It has a negative inotropic effect (decreasing cardiac contractility) but this is usually offset by reflex tachycardia due to vasodilation. Extended-release formulations allow once-daily dosing, improving compliance compared to immediate-release forms that require multiple daily dosing.

Clinical points for pharmacists:

• Monitor for side effects like hypotension, reflex tachycardia, dizziness, and peripheral edema.

• Drug interactions: metabolized by CYP3A4; inhibitors or inducers can alter nifedipine levels.

• Use with caution in patients with severe aortic stenosis or unstable angina.

• Counseling includes adherence, monitoring blood pressure, and recognizing hypotension symptoms.

• Common doses range from 10-120 mg daily depending on formulation and indication.

Nifedipine is effective in managing hypertension and vasospastic or stable angina with a well-established safety profile when used appropriately