What is the recommended dosage of Nicorandil (Nicorandil) for treating angina?

Nicorandil Dosage for Treating Angina

Nicorandil may be considered at a dosage of 10-20 mg twice daily for treating angina, though it is not a first-line agent and its safety in heart failure is uncertain. 1

Treatment Algorithm for Angina

First-Line Therapy

• Beta-blockers are the preferred first-line treatment for angina due to their proven benefits in reducing heart failure hospitalization and mortality 1

Alternative Agents (When Beta-Blockers Cannot Be Used)

1. Ivabradine (Class IIa, Level A) - for patients in sinus rhythm 1
2. Oral or transcutaneous nitrates (Class IIa, Level A) 1
3. Amlodipine (Class IIa, Level A) 1
4. Nicorandil (Class IIb, Level C) - may be considered when beta-blockers cannot be tolerated 1
5. Ranolazine (Class IIb, Level C) 1

Nicorandil Specific Dosing

• Starting dose: 10 mg twice daily 2
• Maintenance dose: 10-20 mg twice daily 2, 3
• Maximum dose: Up to 40 mg daily in divided doses for patients requiring higher doses 4, 2
• Administration: Twice-daily regimen provides sustained efficacy 2

Mechanism and Efficacy

Nicorandil is a potassium channel opener with nitrate-like properties that:

• Causes sustained dilation of both arterial resistance and conductive vessels 4
• Increases coronary blood flow 4
• Has minimal effect on heart rate, blood pressure, or cardiac contractility at clinical doses 4
• Provides balanced peripheral action that decreases both preload and afterload 2

The IONA (Impact Of Nicorandil in Angina) trial demonstrated that nicorandil 20 mg twice daily reduced major coronary events in patients with stable angina, with a 17% reduction in the primary composite endpoint of coronary heart disease death, non-fatal MI, or unplanned hospital admission for cardiac chest pain (p=0.014) 5.

Important Considerations

Safety Profile

• Nicorandil's safety in heart failure is uncertain (Class IIb, Level C) 1
• Main side effects are headaches, which typically occur early in treatment and can be minimized with gradual dose titration 2
• Unlike calcium channel blockers, nicorandil does not have a depressant effect on atrioventricular conduction 4

Combination Therapy

• Nicorandil may be added as a second anti-anginal drug when symptoms persist despite beta-blocker treatment 1
• Caution: Combination of nicorandil with nitrates is NOT recommended due to lack of additional efficacy (Class III, Level C) 1
• Caution: Combination of nicorandil with ivabradine or ranolazine is NOT recommended due to unknown safety (Class III, Level C) 1

Special Populations

• May be effective in patients with rest and effort angina who do not respond to combination therapy with calcium antagonists and oral nitrates 4
• In a pilot study of patients with unstable angina, nicorandil significantly reduced episodes of transient myocardial ischemia and arrhythmias 1

Clinical Pearls

• Nicorandil has shown no evidence of developing tolerance with long-term use (up to 1 year) 2
• The drug has both anti-ischemic and potential cardioprotective properties 5
• Nicorandil is approved in many countries in Europe and Asia but not in the United States 1, 6

When managing angina, always prioritize beta-blockers first when possible, and consider nicorandil as an alternative or add-on therapy when first-line treatments are insufficient or contraindicated.