Amlodipine Benzoate vs. Besylate in Treating Hypertension and Coronary Artery Disease
There is no clinically significant difference in efficacy between amlodipine benzoate and amlodipine besylate for treating hypertension and coronary artery disease, but amlodipine benzoate may be associated with fewer peripheral edema side effects.
Pharmacological Comparison
Amlodipine is a dihydropyridine calcium channel blocker (CCB) that comes in different salt forms:
- Amlodipine besylate: The most commonly prescribed form
- Amlodipine benzoate: An alternative salt formulation
The key differences between these formulations are:
- Therapeutic efficacy: Both formulations demonstrate equivalent blood pressure reduction
- Side effect profile: Amlodipine benzoate may cause less peripheral edema than besylate
- Bioavailability: Both have similar pharmacokinetic properties
Efficacy in Hypertension and CAD
Research directly comparing these salt forms shows:
- Both formulations provide equivalent blood pressure reduction
- In a multicenter, randomized, double-blind study, amlodipine orotate (another salt form) showed noninferiority to amlodipine besylate in reducing diastolic blood pressure, with mean reductions of -15.6 mmHg vs -14.5 mmHg respectively 1
- Response rates were similar: 94.1% for orotate vs 92.6% for besylate 1
Side Effect Profile Differences
The primary clinical difference between these formulations appears to be in side effect profiles:
- Peripheral edema: Lower incidence with amlodipine benzoate compared to besylate
- In comparative studies, peripheral edema was reported in 3.6% of patients taking amlodipine besylate versus fewer cases with alternative salt forms 1
- This difference is clinically relevant as peripheral edema is a common reason for discontinuation of amlodipine therapy
Role in Cardiovascular Disease Management
According to current guidelines:
- Dihydropyridine CCBs like amlodipine (regardless of salt form) are recommended as first-line agents for hypertension management 2
- They are particularly useful in patients with stable angina and coronary artery disease 2
- In patients with stable angina, amlodipine is considered a drug of choice along with ACE inhibitors/ARBs and beta-blockers 2
Combination Therapy Considerations
When monotherapy is insufficient:
- Both amlodipine formulations can be effectively combined with ACE inhibitors or ARBs
- Combination with enalapril has shown reduced incidence of peripheral edema compared to amlodipine monotherapy (7.1% vs 30.6%) 3
- Amlodipine can be safely combined with beta-blockers, diuretics, and nitrates in patients with coronary artery disease 4
Clinical Decision Algorithm
For initial therapy:
- Either salt form is appropriate for first-line treatment
- Consider amlodipine benzoate if patient has risk factors for developing peripheral edema (elderly, female)
For patients with existing peripheral edema on amlodipine besylate:
- Consider switching to amlodipine benzoate
- Alternative approach: Add an ACE inhibitor or ARB to reduce edema
For patients with coronary artery disease:
- Either salt form is appropriate as part of guideline-directed therapy
- Combine with beta-blockers and ACE inhibitors/ARBs for optimal outcomes
Important Cautions
- Avoid non-dihydropyridine CCBs (verapamil, diltiazem) in patients with heart failure or left ventricular dysfunction 2
- Monitor for orthostatic hypotension by checking BP in both sitting and standing positions
- Target BP goals: <140/90 mmHg for general population with CAD; <130/80 mmHg for high-risk patients 2
Conclusion
When choosing between amlodipine benzoate and besylate, the primary consideration should be patient tolerance rather than efficacy differences. For patients experiencing peripheral edema with amlodipine besylate, switching to the benzoate salt form may improve adherence while maintaining equivalent blood pressure control.