Ivabradine Viatris (Ivabradine Oxalate)

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

• Chronic stable angina pectoris: reduces the frequency of angina attacks by decreasing myocardial oxygen demand.
• Heart failure with reduced ejection fraction (NYHA class II–III): improves exercise capacity and may lower hospitalization risk.
• Elevated resting heart rate despite optimal therapy: provides additional heart‑rate control when beta‑blockers alone are insufficient.

• Ivabradine selectively inhibits the funny (If) current in the sino‑atrial node, which slows the spontaneous depolarization of pacemaker cells. This reduction in pacemaker activity lowers heart rate without affecting myocardial contractility or blood pressure, thereby decreasing cardiac oxygen consumption while preserving cardiac output.

Ivabradine may cause a range of adverse reactions, most of which are related to its heart‑rate‑lowering action or visual perception.

Common Side Effects

• Bradycardia: heart rate falls below the intended therapeutic range.
• Visual disturbances (phosphenes): transient luminous phenomena.
• Headache: mild to moderate intensity.
• Dizziness or light‑headedness.
• Fatigue or general weakness.

Serious or Rare Side Effects

• Symptomatic bradycardia requiring medical intervention.
• Atrial fibrillation or other significant arrhythmias.
• Severe hypotension leading to syncope.
• Persistent visual impairment or retinal disturbances.

Before initiating therapy, clinicians should evaluate patient‑specific factors and monitor for potential risks.

• Cardiac monitoring: assess heart rate and rhythm regularly.
• Contraindicated in severe hepatic impairment: avoid use due to altered metabolism.
• Caution in sick‑sinus syndrome or atrioventricular block: may exacerbate conduction abnormalities.
• Use with beta‑blockers only under supervision: risk of excessive bradycardia.
• Pregnancy and lactation: safety not established; avoid unless clearly needed.
• Store at below 25°C: keep in the original container, protect from moisture and light.

Ivabradine can interact with several medicines that affect heart rate or its metabolism.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): may increase ivabradine plasma levels.
• Strong CYP3A4 inducers (e.g., rifampicin, carbamazepine): may reduce efficacy.
• Concomitant bradycardic agents (e.g., beta‑blockers, digoxin) without dose adjustment: risk of severe bradycardia.

Moderate Interactions (Monitor Closely)

• Calcium‑channel blockers diltiazem or verapamil: may modestly raise ivabradine concentrations.
• Macrolide antibiotics (e.g., erythromycin, clarithromycin): potential increase in exposure.
• Antidepressants affecting CYP3A4 (e.g., fluvoxamine): monitor heart rate and adjust if needed.