What is the recommended dosage and administration of nifedipine (calcium channel blocker) for managing hypertension and angina?

Nifedipine Dosing for Hypertension and Angina

For hypertension and angina, use extended-release nifedipine 30-60 mg once daily on an empty stomach, with titration over 7-14 days up to a maximum of 90 mg daily; avoid immediate-release formulations due to safety concerns. 1

Standard Dosing Regimen

Hypertension

• Start with 30 mg once daily of extended-release formulation 1
• Titrate upward over 7-14 days based on therapeutic response and tolerability 1
• Usual maintenance dose: 30-60 mg once daily 1
• Maximum recommended dose: 90 mg daily (doses above this are not recommended) 1
• Administer on an empty stomach 1

Angina Pectoris

• Extended-release formulation: 30-180 mg once daily 2
• For immediate-release (if used): 30-90 mg daily divided into multiple doses 2
• Critical caveat: Immediate-release nifedipine should NOT be used for unstable angina or NSTEMI without concomitant beta-blockade due to increased risk of adverse cardiovascular events 2, 3

Formulation Selection

The extended-release formulation is strongly preferred over immediate-release for several critical reasons 2:

• Provides consistent 24-hour plasma concentrations with once-daily dosing 2
• Superior safety profile compared to immediate-release 2
• Better patient adherence 2
• Immediate-release formulations carry risk of abrupt hypotension and coronary events 3

Tablet Administration

• Swallow tablets whole—do NOT bite, chew, or divide 1
• For patients unable to swallow tablets, consider alternative calcium channel blockers available in liquid formulations rather than immediate-release nifedipine liquid 2

Resistant Hypertension

For patients with resistant hypertension uncontrolled on standard therapy, dihydropyridine calcium channel blockers like nifedipine extended-release are among the most studied and effective agents 2. Some evidence suggests nifedipine may have slightly greater antihypertensive effects than amlodipine, though it is associated with more peripheral edema 2.

Severe Hypertension/Hypertensive Emergencies

In severe hypertension requiring acute management, oral nifedipine is recommended as first-line therapy (along with IV labetalol or oral methyldopa) 4. However, critical caveats apply:

• Immediate-release nifedipine can cause abrupt hypotension leading to neurological and cardiac events 3
• In hypertensive emergencies with acute intracerebral hemorrhage and systolic BP ≥220 mmHg, careful acute BP lowering to <180 mmHg should be considered 4
• Immediate BP lowering is NOT recommended for systolic BP <220 mmHg in acute intracerebral hemorrhage 4

Common Adverse Effects

Dose-related vasodilatory side effects include 2:

• Peripheral edema (more common than with amlodipine)
• Headache
• Flushing
• Dizziness
• Hypotension
• Nausea and constipation

These effects are generally mild to moderate, transient, and diminish with continued treatment 5.

Critical Contraindications and Warnings

Nifedipine is contraindicated in 3:

• Recent myocardial infarction
• Unstable angina (unless combined with beta-blocker) 2, 3

Avoid co-administration with grapefruit juice, which affects drug metabolism 1.

Discontinuation

If discontinuation is necessary, gradually taper the dose under close physician supervision rather than abrupt cessation 1.

Dose Reduction Considerations

Patients well-controlled on 30 mg daily may potentially be reduced to 20 mg daily with maintained efficacy, particularly in lower body weight patients or when used as adjunct therapy 6. However, this should only be attempted in patients with documented stable control for ≥3 months 6.