Ivabradine (Ivabradine Hydrochloride)

Ivabradine acts on the cardiac If current to lower heart rate in cardiovascular disease.

• Chronic stable angina pectoris: improves exercise tolerance and reduces frequency of angina episodes.
• Heart failure with reduced ejection fraction: lowers resting heart rate and may lessen symptoms and hospitalisations.
• Patients with sinus rhythm and resting heart rate ≥75 bpm: provides heart‑rate reduction when beta‑blocker therapy is insufficient.

• Ivabradine selectively inhibits the funny (If) current in the sinoatrial node, which controls spontaneous depolarisation. By blocking this inward sodium/potassium mixed current, the drug slows the pacemaker activity without affecting myocardial contractility, resulting in a reduction of heart rate while preserving cardiac output.

Ivabradine may cause a range of adverse reactions, most of which are mild and reversible.

Common Side Effects

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

Serious or Rare Side Effects

• Symptomatic bradycardia requiring medical intervention.
• Atrial fibrillation or other arrhythmias.
• Severe hypotension.
• Symptomatic heart block.
• Persistent visual disturbances.
• Elevated hepatic enzymes.

Before prescribing Ivabradine, clinicians should consider several safety aspects.

• Cardiovascular assessment: confirm heart rate and sinus rhythm.
• Concomitant bradycardic agents: monitor for excessive slowing of heart rate.
• CYP3A4 inhibitors: avoid strong inhibitors or adjust therapy.
• Severe hepatic impairment: contraindicated due to altered metabolism.
• Pregnancy and lactation: safety not established; use only if benefits outweigh risks.
• Store at ambient temperature: keep below 25 °C, protect from moisture and light in the original container.

Ivabradine interacts with several drug classes that may alter its efficacy or safety.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): may increase plasma levels.
• Other heart‑rate‑lowering agents (beta‑blockers, digoxin, diltiazem, verapamil): risk of profound bradycardia.
• Other If channel inhibitors: additive effect on heart rate.

Moderate Interactions (Monitor Closely)

• Moderate CYP3A4 inhibitors (e.g., fluconazole): may modestly raise concentrations.
• CYP3A4 inducers (e.g., rifampicin, carbamazepine): may reduce effectiveness.
• Diuretics causing electrolyte imbalance: may predispose to arrhythmias.
• Antihypertensive agents: monitor blood pressure for additive hypotensive effect.