Cardiovascular
Ivabradine
A heart-rate-lowering drug — Slows the heart in heart failure and angina without lowering blood pressure — only in normal (sinus) rhythm.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
What it is
Ivabradine lowers the heart rate in chronic heart failure and in angina, used particularly when beta-blockers are insufficient or not tolerated. It is added to, rather than replacing, standard treatment.
How it works
It selectively slows the natural pacemaker cells of the heart (the "funny current" in the sinus node), reducing the heart rate without affecting the heart's pumping force or blood pressure. Because it acts only on the sinus node, it does nothing useful when the rhythm is atrial fibrillation.
In practice
In practice ivabradine occupies a specific niche: it slows the heart rate purely by acting on the heart's natural pacemaker, which makes it useful as an add-on in heart failure (and in angina) for patients who remain symptomatic with a fast resting rate despite a beta-blocker, or who cannot tolerate beta-blockers. Two conditions define its use. First, it only works in normal "sinus" rhythm — it has no useful effect in atrial fibrillation. Second, the heart rate must be high enough to begin with, and the drug is titrated to a target rate, avoiding excessive slowing. Its characteristic and harmless side-effect is transient visual brightness or shimmering (phosphenes), worth mentioning so patients are not alarmed. It interacts with drugs that affect its metabolism and with other rate-slowing agents.
Examples
Practical use
How to take it & use it well
- Take ivabradine twice a day with food, ideally with your morning and evening meals, at about the same times each day.
- Attend appointments to check your heart rate and rhythm, as the dose is adjusted to keep your resting heart rate in a safe range.
- Tell your prescriber if you develop a very slow pulse, dizziness, fainting or breathlessness, as the dose may need changing.
- Avoid grapefruit and grapefruit juice, as they can raise ivabradine levels and increase side effects.
- Be aware you may notice brief flashes or halos of brightness in your vision (phosphenes), which are usually harmless but worth mentioning.
- Do not stop suddenly without advice, and report any new palpitations or irregular heartbeat to your team.
Common uses
- Chronic heart failure (add-on, in sinus rhythm with a raised heart rate)
- Angina where beta-blockers are insufficient or unsuitable
Monitoring
- Heart rate and rhythm (confirm sinus rhythm)
- Symptoms and tolerability
- For new atrial fibrillation
Weighing it up
Advantages & disadvantages
Advantages
- Slows the heart rate to ease the workload on the heart in certain types of heart failure and angina.
- Can reduce symptoms and the risk of hospital admission in suitable people with heart failure.
- Useful when beta-blockers cannot be used or are not enough to control the heart rate.
- Lowers heart rate without lowering blood pressure as much as some other rate-lowering medicines.
Disadvantages
- Only works in people whose heart beats in a normal (sinus) rhythm, not in conditions like atrial fibrillation.
- Can cause temporary visual symptoms such as flashes or halos of light, particularly early in treatment.
- May slow the heart too much or cause an irregular rhythm, so heart rate must be monitored.
- Can cause headache and dizziness in some people.
Key safety principles
What to watch for
- Only effective in normal (sinus) rhythm — not in atrial fibrillation.
- Avoid excessive heart-rate slowing; needs an adequate baseline heart rate to start.
- Transient visual brightness (phosphenes) is common and harmless; interacts with several drugs and other rate-slowing agents.
Key interactions
What to avoid or check alongside
- Medicines that strongly raise ivabradine levels, such as the antibiotics clarithromycin and erythromycin and the antifungal ketoconazole, increase the risk of a dangerously slow heart.
- Other heart-rate-lowering drugs, including some calcium channel blockers like verapamil and diltiazem, can slow the heart too much when combined.
- Grapefruit juice raises ivabradine levels and should be avoided.
- Medicines that can disturb the heart's electrical rhythm may add to the risk of irregular heartbeat.
- Some medicines that lower ivabradine levels, such as rifampicin, can reduce its effect.
Patient & carer advice
- You may notice brief flashes of brightness in your vision — this is harmless
- It is added to your other heart medicines, not a replacement
- Tell us if your heartbeat becomes irregular
Use with
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Answers
Ivabradine: frequently asked questions
Does ivabradine work if I have an irregular heartbeat?
No. Ivabradine only works when the heart is in a normal sinus rhythm. It is not effective in conditions like atrial fibrillation, where the rhythm is irregular.
What are the visual flashes some people get on ivabradine?
These are called phosphenes, brief flashes or halos of increased brightness, often triggered by changes in light. They are usually harmless, tend to ease with time, but should be mentioned to your team.
Why does my heart rate need monitoring on ivabradine?
The medicine deliberately slows the heart, so your team checks your rate to make sure it does not become too slow and to watch for any irregular rhythm, adjusting the dose as needed.
Should I avoid grapefruit with ivabradine?
Yes. Grapefruit and its juice can raise ivabradine levels in the blood and increase the chance of side effects such as an overly slow heart, so they are best avoided.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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