Cardiovascular
Medicines for Heart block
A problem with the heart's electrical signalling that slows or blocks the heartbeat — ranging from harmless to serious, with a pacemaker needed for significant cases.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Heart block?
Heart block is a problem with the electrical signals that coordinate the heartbeat, where the signal travelling from the upper to the lower chambers of the heart is slowed or blocked. It is graded by severity.
- How it is treated: Treatment depends entirely on the severity and symptoms.
- Self-care: Attending recommended monitoring, reporting symptoms such as dizziness, blackouts or a very slow pulse, and following pacemaker check-ups (for those who have one) are the main practical steps.
- When to seek help: See a GP about dizziness, blackouts, unusual tiredness or a very slow pulse.
What it is
Heart block is a problem with the electrical signals that coordinate the heartbeat, where the signal travelling from the upper to the lower chambers of the heart is slowed or blocked. It is graded by severity. First-degree heart block is a slight delay, usually causing no symptoms and often needing no treatment. Second-degree block is a partial block where some signals do not get through, which can cause skipped beats, dizziness or tiredness. Third-degree (complete) heart block, where no signals get through, can cause a very slow heartbeat, blackouts, breathlessness and can be dangerous. Causes include ageing of the heart's electrical system, heart disease, some medicines, and occasionally being present from birth or very fit. It is diagnosed on an ECG.
How it is treated
Treatment depends entirely on the severity and symptoms. Mild (first-degree) heart block usually needs no treatment, just occasional monitoring. More significant heart block that causes symptoms or is high-grade is treated by implanting a pacemaker — a small device that keeps the heartbeat regular and is very effective. Any reversible cause, such as a contributing medicine, is reviewed. Complete heart block, especially with symptoms, is treated urgently, often with a pacemaker. Underlying heart conditions are managed alongside. Care is guided by a cardiology team, and people with pacemakers have regular checks.
For this condition, these medicines
Medicine classes used for Heart block
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Beyond medication
Lifestyle and self-care
Attending recommended monitoring, reporting symptoms such as dizziness, blackouts or a very slow pulse, and following pacemaker check-ups (for those who have one) are the main practical steps. Managing any underlying heart condition supports heart health.
When to get help
When to see a doctor
See a GP about dizziness, blackouts, unusual tiredness or a very slow pulse. Call 999 for fainting with injury, sudden severe breathlessness, chest pain, or collapse, which can occur with serious heart block.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Heart block: frequently asked questions
Is heart block always serious?
No. Mild (first-degree) heart block often causes no symptoms and needs no treatment. More significant heart block, especially complete heart block with symptoms, can be serious and is usually treated with a pacemaker.
How is significant heart block treated?
Usually by implanting a pacemaker, a small device that keeps the heartbeat regular and is very effective. Any reversible causes, such as certain medicines, are also reviewed.
Sources
Where this is drawn from
- NHS — Heart block
- British Heart Foundation — Heart block
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