Ivabradine

Ivabradine acts on the cardiac sinus node to lower heart rate, benefiting conditions where heart‑rate reduction improves outcomes.

• Chronic stable angina: reduces the frequency of angina attacks by decreasing myocardial oxygen demand.
• Heart failure with reduced ejection fraction: improves symptoms and lowers hospitalization risk by controlling heart rate.
• Patients intolerant to beta‑blockers: provides heart‑rate control without beta‑adrenergic blockade.

• Ivabradine selectively inhibits the funny (If) current in the sinoatrial node, which slows the spontaneous depolarization of pacemaker cells. This reduction in the If current lowers heart rate without affecting myocardial contractility, ventricular repolarization, or systemic blood pressure, allowing improved cardiac efficiency in angina and heart‑failure settings.

Adverse reactions may vary in frequency and severity.

Common Side Effects

• Bradycardia: heart rate slower than intended.
• Visual disturbances (phosphenes): transient luminous phenomena.
• Headache.
• Dizziness.
• Fatigue.

Serious or Rare Side Effects

• Symptomatic bradycardia requiring medical intervention.
• Atrial fibrillation or other arrhythmias.
• Severe hypotension.
• Persistent visual impairment.
• Heart block requiring pacing.

Careful assessment and monitoring are required before and during therapy.

• Heart‑rate monitoring: obtain baseline rate and reassess after dose changes.
• Hepatic impairment: avoid in severe liver disease; adjust if moderate.
• CYP3A4 inhibitors: use caution with strong inhibitors that may raise plasma levels.
• Concomitant bradycardic agents: avoid combining with beta‑blockers or digoxin unless clinically justified.
• Pregnancy and lactation: safety unknown; prescribe only if benefits outweigh risks.
• Store at ambient temperature below 25°C: keep in the original pack, protect from moisture.

Ivabradine may interact with several drug classes, requiring attention to avoid adverse outcomes.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): can markedly increase Ivabradine exposure.
• Concomitant bradycardic agents (beta‑blockers, digoxin): may cause excessive heart‑rate reduction.
• Other If channel inhibitors: additive effect on heart‑rate lowering.

Moderate Interactions (Monitor Closely)

• Moderate CYP3A4 inhibitors (e.g., diltiazem, verapamil): may modestly raise levels.
• CYP3A4 inducers (e.g., rifampicin, carbamazepine): may reduce efficacy.
• Antihypertensives: monitor blood pressure for additive hypotensive effect.