What is the appropriate dosing for Adalat (nifedipine) 30 mg XL twice daily in patients with hypertension or angina?

Nifedipine (Adalat) Dosing for Hypertension and Angina

Adalat (nifedipine) 30 mg XL twice daily is not an appropriate dosing regimen for hypertension or angina. The extended-release formulation should be administered once daily, not twice daily. 1

Appropriate Dosing for Nifedipine XL

• For hypertension and angina, the extended-release formulation (XL/CC) should be administered once daily, with a dose range of 30-90 mg daily 1
• The maximum recommended dose of extended-release nifedipine for angina is 180 mg once daily 1
• Twice-daily dosing of extended-release formulations is not recommended and may increase the risk of adverse effects 1, 2

Pharmacokinetic Considerations

• Extended-release nifedipine formulations (like Adalat XL) are designed to provide 24-hour blood pressure control with once-daily dosing 2, 3
• Studies comparing extended-release formulations have shown effective 24-hour blood pressure control with once-daily administration 2
• Twice-daily administration of nifedipine can cause excessive blood pressure lowering during nighttime hours when blood pressure is already naturally lower 3

Clinical Recommendations

• For hypertension management:

  • Start with nifedipine XL 30 mg once daily 1
  • Titrate to 60-90 mg once daily if needed for blood pressure control 1, 4
  • Consider as part of combination therapy with other antihypertensive agents if monotherapy is insufficient 4

• For angina management:

  • Start with nifedipine XL 30 mg once daily 1
  • May titrate up to 90 mg once daily based on symptoms 1
  • Consider combination with beta-blockers for optimal angina control 4, 5

Adverse Effects and Monitoring

• Common side effects include hypotension, dizziness, flushing, headache, and peripheral edema 1
• Monitor for excessive blood pressure reduction, especially when initiating therapy or increasing dose 1, 6
• Avoid immediate-release nifedipine for unstable angina unless combined with beta-blockers due to risk of reflex tachycardia 1

Alternative Regimens

• If twice-daily dosing is desired for a calcium channel blocker, consider switching to a different agent like amlodipine (5-10 mg once daily) 7
• For patients with both hypertension and angina, a long-acting dihydropyridine calcium channel blocker is recommended as part of the treatment regimen 4

Special Considerations

• In hypertensive emergencies, intravenous agents are preferred over oral nifedipine 4
• For patients with diabetes and hypertension, calcium channel blockers are one of the recommended drug classes along with ACE inhibitors, ARBs, and thiazide-like diuretics 4
• In patients with resistant hypertension, a combination of ACE inhibitor/ARB, thiazide-like diuretic, and dihydropyridine calcium channel blocker is recommended before adding additional agents 4