Indications
Ivabradine is used for two heart conditions in adults:
- Long-term (stable) angina, the chest pain that comes on with effort, in people with a normal heart rhythm whose heart rate stays too fast, either because they cannot take a beta-blocker or as an add-on to one.
- Long-term heart failure with a weak heart pump, when the resting heart rate stays at about 70 to 75 beats per minute or above despite standard treatment.
How It Works
Ivabradine works on the heart’s natural pacemaker (the sinus node) and slows the heart rate. A slower heart needs less oxygen and has more time to fill, which reduces angina and helps a failing heart. Unlike many heart medicines, it does not lower blood pressure or weaken the heart’s pumping force.
Dosage and Administration
Adults: usually 5 mg twice a day, taken with the morning and evening meals. After 2 to 4 weeks the doctor may raise it to 7.5 mg twice a day or lower it to 2.5 mg twice a day depending on the resting heart rate. People aged 75 years or over may start on 2.5 mg twice a day. Always follow the dose prescribed; do not change it yourself.
Interactions
- Must not be taken with strong enzyme blockers such as Ketoconazole, Itraconazole, Clarithromycin, oral Erythromycin, Ritonavir and Nelfinavir, which raise ivabradine levels sharply.
- Do not combine with Diltiazem or Verapamil, which also slow the heart.
- Avoid grapefruit juice.
- Medicines that affect heart rhythm (QT-prolonging medicines such as some antiarrhythmics, antipsychotics and antibiotics) and water tablets that lower potassium need extra care.
- St John’s wort can reduce its effect.
Contraindications
- Resting heart rate below 70 beats per minute before starting, or very slow heart rate.
- Recent heart attack, unstable angina, cardiogenic shock, or heart failure that has suddenly worsened.
- Very low blood pressure, sick sinus syndrome, certain heart blocks, or dependence on a pacemaker.
- Severe liver disease.
- Pregnancy, breastfeeding, and women who could become pregnant and are not using reliable contraception.
- Use with the strong enzyme blockers, Diltiazem or Verapamil listed above, or allergy to ivabradine.
Side Effects
Common:
- Brief bright spots or flashes of light in part of the vision (luminous phenomena), usually in the first 2 months and often fading with time.
- Slow heart rate, dizziness, headache and blurred vision.
- Irregular heartbeat (atrial fibrillation).
Get urgent medical help if you have a very slow pulse with fainting or severe dizziness, a fast or irregular heartbeat, new or worse chest pain, or sudden breathlessness.
Pregnancy and Lactation
Ivabradine may harm an unborn baby and must not be used in pregnancy. Women who could become pregnant should use reliable contraception. Do not breastfeed while taking it.
Precautions and Warnings
- The doctor will check your heart rate regularly; tell them if your pulse feels very slow or irregular.
- The light effects can come on suddenly, so take care when driving, especially at night, until you know how you react.
- It does not treat irregular heart rhythms and is not for sudden chest pain attacks.
- Tell the doctor about liver or kidney problems and about any eye disease affecting the retina.
Overdose
Too much can cause a severe, long-lasting slow heart rate and low blood pressure. Seek emergency medical help at once.
Therapeutic Class
Antianginal and heart failure medicine (sinus node If current inhibitor).
Storage
Store below 30°C in a dry place, away from light and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.