Nifedipine Tablets: Managing Blood Pressure and Heart Conditions

Mechanism of Action

Nifedipine is a calcium channel blocker belonging to the dihydropyridine subclass. It exerts its therapeutic effects by inhibiting voltage-gated L-type calcium channels in vascular smooth muscle and myocardial cells. This blockage prevents the entry of calcium ions into cells during depolarization, reducing peripheral arterial vascular resistance and dilating coronary arteries. As a result, it reduces systemic blood pressure and increases myocardial oxygen delivery.

Uses

Nifedipine tablets are primarily used for:

• Chronic stable angina: Reduces the frequency of angina attacks and increases exercise tolerance.
• Vasospastic angina: Effective in preventing coronary artery spasms.
• Hypertension: Used as monotherapy or in combination with other antihypertensive agents.
• Off-label uses: Including Raynaud's phenomenon, severe hypertension during pregnancy, high altitude pulmonary edema, and pulmonary arterial hypertension.

Dosage and Administration

Chronic Stable Angina:

• Immediate-release: 10 to 20 mg three times daily; maximum dose of 180 mg per day.
• Extended-release: 30 or 60 mg daily; maximum dose of 120 mg per day.
• Vasospastic Angina:
• Extended-release: 30 or 60 mg daily; maximum dose of 120 mg per day.
• Hypertension:
• Extended-release: 30 or 60 mg daily; maximum dose of 120 mg per day.
• Hypertensive Emergency During Pregnancy or Postpartum Period:
• Immediate-release: 10 mg; may repeat with a 20 mg dose in 20 minutes.
• Administration:
• Nifedipine is available in both immediate and extended-release formulations. Immediate-release formulations can be taken without regard to meals, while some extended-release preparations require ingestion on an empty stomach.

Storage

Nifedipine tablets should be stored at room temperature, typically between 15°C and 30°C (59°F to 86°F), and protected from light.