What is the recommended dosage and treatment protocol for Amlodipine (calcium channel blocker) in managing hypertension and angina?

Amlodipine Dosage and Treatment Protocol for Hypertension and Angina

For hypertension management, amlodipine should be initiated at 5 mg once daily, with titration to 10 mg daily if necessary for adequate blood pressure control. For angina management, the same dosing applies, with 5-10 mg once daily providing effective symptom relief for a full 24 hours 1.

Dosing Recommendations

Hypertension

• Initial dose: 5 mg once daily
• Maintenance dose: 5-10 mg once daily
• Maximum dose: 10 mg once daily
• Timing: Can be taken at any time of day, but consistent timing improves adherence 2

Angina

• Initial dose: 5 mg once daily
• Titration: Increase to 10 mg once daily if angina persists after 2 weeks
• Efficacy: Increases exercise time by 7.9% (38 sec) at 5 mg dose and 12.8% (63 sec) at 10 mg dose 1

Treatment Algorithm for Hypertension

1. First-line therapy options:

   • ACE inhibitor or ARB
   • Dihydropyridine CCB (amlodipine)
   • Thiazide or thiazide-like diuretic 2

2. Combination therapy:

   • Most patients with confirmed hypertension (≥140/90 mmHg) should receive combination therapy as initial treatment
   • Preferred combinations include a RAS blocker (ACE inhibitor or ARB) with either amlodipine or a diuretic 2
   • Fixed-dose single-pill combinations are recommended for improved adherence

3. Treatment targets:

   • For most adults: 120-129 mmHg systolic BP
   • For patients with CAD: <140/90 mmHg (with consideration of <130/80 mmHg in selected high-risk patients) 2

Treatment Algorithm for Angina

1. First-line therapy:

   • Beta-blockers are preferred first-line treatment for angina due to their mortality benefit 2

2. When beta-blockers cannot be used:

   • Amlodipine is recommended as an alternative (Class IIa, Level A) 2
   • Other alternatives include ivabradine or nitrates

3. Add-on therapy when symptoms persist:

   • Add amlodipine to beta-blocker therapy (Class I, Level A) 2
   • Other options include adding nitrates or ivabradine

Special Considerations

Post-CABG Hypertension Management

• Beta-blockers should be reinstituted as soon as possible
• ACE inhibitors/ARBs should be reinstituted once the patient is stable
• For uncontrolled hypertension, add amlodipine (if angina is present) 3

Patients with Heart Failure

• Amlodipine has been shown to be safe in patients with NYHA Class II/III heart failure 1
• No evidence of worsened heart failure in clinical trials
• However, other CCBs like diltiazem and verapamil should be avoided in patients with LV dysfunction 2

Patients on Bevacizumab

• For antihypertensive-naive patients with BP ≥150/95 mmHg, amlodipine 5 mg daily is recommended as initial therapy 2

Common Pitfalls and Caveats

1. Avoid rapid-release, short-acting dihydropyridines (e.g., immediate-release nifedipine) in the absence of beta-blockade due to increased adverse potential 2

2. Drug interactions:

   • Combining amlodipine with beta-blockers is generally safe and effective
   • Non-dihydropyridine CCBs (diltiazem, verapamil) should be used with caution when combined with beta-blockers due to risk of bradyarrhythmias and heart failure 2

3. Side effects to monitor:

   • Peripheral edema (most common)
   • Headache
   • Flushing
   • Dizziness 2

4. Adherence considerations:

   • Once-daily dosing of amlodipine provides better compliance than multiple daily dosing regimens 4
   • The long half-life (40-60 hours) ensures 24-hour coverage with minimal fluctuation between doses 5

Amlodipine's unique pharmacokinetic profile, including gradual onset of action, long half-life, and once-daily dosing, makes it an excellent choice for both hypertension and angina management with high patient adherence and minimal side effects.