Is Norvasc (Amlodipine) 10mg twice daily effective for managing hypertension and coronary artery disease?

Norvasc (Amlodipine) 10mg Twice Daily Is Not Effective for Hypertension and Coronary Artery Disease

Amlodipine 10mg twice daily is not recommended for managing hypertension and coronary artery disease as it exceeds the FDA-approved dosing and lacks evidence supporting efficacy or safety at this dose. 1

Appropriate Dosing for Amlodipine

• Amlodipine is FDA-approved as a once-daily medication with dosing ranging from 2.5-10mg daily for hypertension and coronary artery disease 1
• The FDA drug label specifically documents effectiveness of amlodipine at 5-10mg once daily dosing for chronic stable angina 1
• Clinical studies have demonstrated that the long half-life of amlodipine allows for effective 24-hour blood pressure control with once-daily dosing 2

Evidence for Dihydropyridine CCBs in Coronary Artery Disease

• Dihydropyridine calcium channel blockers (CCBs) like amlodipine are considered appropriate drugs of choice for patients with stable angina and coronary artery disease 3
• In patients with hypertension and stable coronary artery disease, dihydropyridine CCBs can be added to the basic regimen of β-blocker, ACE inhibitor, and thiazide diuretic if either angina or hypertension remains uncontrolled 3
• Long-term studies have shown that amlodipine at appropriate once-daily dosing (mean daily dose 8.2mg) significantly reduces angina attack rate and improves exercise performance 2

Recommended Treatment Approach for Hypertension with CAD

1. First-line therapy should include:

   • β-blocker (especially with prior MI) 3
   • ACE inhibitor or ARB (particularly with prior MI, LV dysfunction, diabetes, or CKD) 3
   • Thiazide or thiazide-like diuretic 3

2. If blood pressure remains uncontrolled:

   • Add a long-acting dihydropyridine CCB like amlodipine at appropriate dosing (5-10mg once daily) 3, 1
   • Consider combination therapy as a single-pill to improve adherence 4

Blood Pressure Targets

• For patients with coronary artery disease, the target blood pressure is <140/90 mmHg (Class IIa; Level of Evidence B) 3
• A lower target (<130/80 mmHg) may be considered in some individuals with CAD, previous stroke, or CAD risk equivalents (Class IIb; Level of Evidence B) 3

Common Pitfalls to Avoid

• Exceeding maximum recommended doses of medications, which increases risk of adverse effects without proven additional benefit 1
• Using twice-daily dosing for medications designed for once-daily administration, which may reduce adherence without improving outcomes 4
• Failing to consider combination therapy with complementary mechanisms when blood pressure remains uncontrolled 4
• Combining non-dihydropyridine CCBs with β-blockers, which should be used with caution due to increased risk of bradyarrhythmias and heart failure 3

Special Considerations

• In patients with heart failure and reduced ejection fraction, non-dihydropyridine CCBs (verapamil and diltiazem) should be avoided 3
• For patients with hypertension and heart failure with preserved ejection fraction, dihydropyridine CCBs may be effective to minimize symptoms 3
• In elderly patients, monitor for orthostatic changes and avoid excessively low diastolic blood pressure (<65 mmHg) 3

In conclusion, while amlodipine is an effective medication for managing hypertension and coronary artery disease, the 10mg twice daily regimen exceeds the FDA-approved dosing and lacks evidence supporting its efficacy or safety. The recommended approach is to use amlodipine at 5-10mg once daily, potentially in combination with other antihypertensive medications as needed to achieve blood pressure targets.