What is the recommended use and dosage of nifedipine for treating hypertension and angina?

Nifedipine Use and Dosage for Hypertension and Angina

Extended-release nifedipine is recommended for hypertension at an initial dose of 30 mg once daily, titrated to 30-60 mg daily as needed, while immediate-release nifedipine should NOT be used for hypertension or unstable angina without concomitant beta-blocker therapy due to increased cardiovascular risk. 1, 2

Indications and Formulations

Hypertension

• Nifedipine extended-release (ER) is effective for mild to moderate hypertension 3
• Dosing:
  • Initial: 30 mg once daily on an empty stomach 2
  • Titration: Over 7-14 days based on efficacy and safety 2
  • Maintenance: 30-60 mg once daily 2
  • Maximum: Doses above 90 mg daily are not recommended 2

Angina

• Nifedipine is indicated for:
  • Stable angina (extended-release formulation) 4
  • Vasospastic angina (Prinzmetal's) 5
• Important contraindication: Immediate-release nifedipine should not be administered to patients with unstable angina or acute coronary syndromes without beta-blocker therapy 5, 1
• Long-acting calcium channel blockers are specifically recommended for coronary artery spasm 5

Administration Guidelines

• Extended-release tablets must be swallowed whole, not bitten or divided 2
• Should be taken on an empty stomach 2
• Avoid co-administration with grapefruit juice 2
• If discontinuation is necessary, dosage should be decreased gradually under physician supervision 2

Contraindications and Precautions

• Immediate-release nifedipine is contraindicated in:

  • Unstable angina without beta-blocker therapy 5, 1
  • Recent myocardial infarction 1, 6
  • Severe left ventricular dysfunction 1
  • Heart failure with reduced ejection fraction 1
  • Advanced aortic stenosis 1
  • Pulmonary edema 1

• Use with caution in:

  • Elderly patients 1
  • Hepatic impairment 1
  • Renal disease 1

Adverse Effects

• Most common adverse effects:

  • Peripheral edema (8.1%) 3
  • Headache (12.2%) 3
  • Dizziness (2.9%) 3
  • Flushing 3
  • Hypotension 6

• Adverse effects are typically:

  • Dose-related 4
  • Most frequent during the first 3 weeks of treatment 3
  • Generally mild to moderate and transient 4

Clinical Pearls

1. Safety warning: Immediate-release nifedipine can cause dangerous hypotension leading to neurological and cardiac events, particularly when used for hypertensive emergencies 6

2. Combination therapy:

   • When used for angina, nifedipine is most effective when combined with a beta-blocker 6
   • Dihydropyridine calcium channel blockers (like nifedipine) are preferred over non-dihydropyridines when combined with beta-blockers to avoid excessive bradycardia 1

3. Formulation differences:

   • Sustained-release formulations have better tolerability than immediate-release, particularly regarding reflex tachycardia 4
   • Extended-release formulations maintain therapeutic blood levels over 24 hours, allowing once-daily dosing 3

4. Monitoring:

   • Monitor for peripheral edema, especially during initial treatment 1
   • Watch for hypotension, particularly with dose increases 6

By following these guidelines and precautions, nifedipine can be effectively and safely used for the management of hypertension and specific types of angina when appropriately prescribed.