What is the recommended dosage and management for extended release Calcium Channel Blockers (CCBs) in treating conditions like hypertension or angina?

Dosage and Management of Extended Release Calcium Channel Blockers for Hypertension and Angina

For extended release calcium channel blockers (CCBs), the recommended dosage is 5-10 mg once daily for amlodipine, 30-180 mg once daily for slow-release nifedipine, and 120-480 mg once daily for slow-release verapamil or diltiazem, with selection based on patient characteristics and comorbidities. 1, 2

Types of Extended Release CCBs and Their Properties

Extended release CCBs fall into two main categories:

1. Dihydropyridines (primarily vasodilatory effects):

   • Amlodipine: 5-10 mg once daily (long-acting)
   • Felodipine: 5-10 mg once daily (long-acting)
   • Slow-release nifedipine: 30-180 mg once daily

2. Non-dihydropyridines (effects on heart rate and conduction):

   • Slow-release diltiazem: 120-360 mg once daily
   • Slow-release verapamil: 120-480 mg once daily

Dosing Recommendations by Agent

Amlodipine

• Initial dose: 5 mg once daily
• Maximum dose: 10 mg once daily
• Special populations: Start with 2.5 mg in elderly, fragile patients, or those with hepatic insufficiency 1
• Titration: Wait 7-14 days between dose adjustments 1

Slow-release Nifedipine

• Dose range: 30-180 mg once daily 2
• Warning: Immediate-release nifedipine should be avoided due to increased risk of adverse cardiovascular events 2, 3

Slow-release Diltiazem

• Dose range: 120-360 mg once daily 2

Slow-release Verapamil

• Dose range: 120-480 mg once daily 2

Selection Algorithm Based on Clinical Scenario

1. For uncomplicated hypertension:

   • First choice: Long-acting dihydropyridine CCB (amlodipine 5-10 mg daily or felodipine 5-10 mg daily) 2, 3

2. For hypertension with angina:

   • First choice: Long-acting dihydropyridine CCB (amlodipine 5-10 mg daily) 1
   • Alternative: Non-dihydropyridine CCB (diltiazem or verapamil) if heart rate control is also needed 2

3. For hypertension with heart failure:

   • First choice: Amlodipine 5-10 mg daily (only after optimizing ACE inhibitors/ARBs, beta-blockers, and diuretics) 3
   • Avoid non-dihydropyridine CCBs (diltiazem, verapamil) in patients with LV dysfunction 2, 3

4. For hypertension with atrial fibrillation:

   • First choice: Diltiazem slow-release (120-360 mg daily) 3

5. For vasospastic angina:

   • Any CCB is appropriate (all have similar coronary vasodilatory effects) 3
   • Amlodipine 5-10 mg daily has shown efficacy in reducing attacks by approximately 4/week 1

Management Principles

1. Monitoring:

   • Blood pressure response
   • Heart rate (especially with non-dihydropyridines)
   • Signs of peripheral edema (common side effect)
   • Symptoms of constipation (especially with verapamil)

2. Combination therapy:

   • CCBs can be combined with other antihypertensives when monotherapy is insufficient 2
   • Dihydropyridine CCBs can be safely added to beta-blockers, ACE inhibitors, and diuretics 2
   • Use caution when combining non-dihydropyridine CCBs with beta-blockers due to risk of bradyarrhythmias 2

3. Side effect management:

   • For peripheral edema: Consider dose reduction or switching to another class
   • For constipation (with verapamil): Increase fluid and fiber intake
   • For headache or flushing: These typically resolve with continued therapy

Important Cautions and Contraindications

1. Avoid immediate-release, short-acting nifedipine in patients with unstable angina/NSTEMI except with concomitant beta-blockade 2

2. Avoid verapamil and diltiazem in patients with:

   • Pulmonary edema
   • Severe LV dysfunction
   • Heart failure 2, 3

3. Use caution when combining beta-blockers with non-dihydropyridine CCBs due to risk of:

   • Significant bradyarrhythmias
   • Heart failure 2

4. Dosage adjustment needed in:

   • Elderly patients
   • Patients with hepatic insufficiency
   • Patients taking multiple medications with potential interactions 1

Extended release CCBs are effective for both hypertension and angina, with once-daily dosing improving adherence. Amlodipine, with its long half-life (36 hours), provides better morning blood pressure control compared to shorter-acting agents 4, which is particularly important as cardiovascular events often peak in the morning hours.