Cardiovascular
Antiplatelet drugs
e.g. aspirin, clopidogrel — Reduce clot formation in arterial disease — used after heart attack, stroke and stenting.
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
Antiplatelet drugs reduce the stickiness of platelets to prevent arterial clots that cause heart attacks and strokes. They are used for secondary prevention and around procedures such as coronary stenting.
How it works
They interfere with the signals platelets use to clump together — aspirin by blocking thromboxane production, clopidogrel and similar drugs by blocking the P2Y12 receptor — making clots less likely to form on damaged arteries.
In practice
In practice antiplatelets are about arterial protection, distinct from the anticoagulants used in AF and venous clots. Single therapy is common for secondary prevention; dual therapy after stents or acute coronary syndromes is time-limited and should be reviewed at the planned stop date. Always weigh bleeding risk, consider gastroprotection, and be cautious when an antiplatelet and an anticoagulant are needed together.
Examples
Practical use
How to take it & use it well
- Take it at the same time each day, and take aspirin with or after food to reduce stomach irritation.
- Swallow tablets whole with water unless told otherwise; some aspirin is coated to protect the stomach and should not be crushed.
- Do not stop taking it without advice, especially after a stent or heart attack, as stopping early can raise the risk of a serious clot.
- If you miss a dose, take it when you remember the same day, but skip it if it is nearly time for the next one. Do not double up.
- Watch for unusual bruising, nosebleeds, blood in urine or stools, or bleeding that will not stop, and seek advice if it happens.
- Tell any dentist, doctor or surgeon that you take an antiplatelet before any procedure.
Common uses
- Secondary prevention after MI or ischaemic stroke/TIA
- After coronary stenting (dual therapy, time-limited)
- Peripheral arterial disease
Monitoring
- Signs of bleeding
- Whether dual therapy can step down to single at the review date
Weighing it up
Advantages & disadvantages
Advantages
- They reduce the risk of heart attacks and strokes by stopping platelets from forming clots.
- They are essential after stents and heart attacks to keep arteries open.
- They are usually taken once a day and are easy to use.
- Aspirin and clopidogrel are inexpensive and widely available on the NHS.
- They have strong evidence for protecting people with established heart and artery disease.
Disadvantages
- Like all blood thinners, they increase the risk of bleeding and bruising.
- Aspirin can irritate the stomach and cause ulcers, especially with long-term use.
- Taking two antiplatelets together raises bleeding risk further.
- They can complicate surgery and dental procedures, sometimes needing to be paused.
- They are not suitable for everyone, including some people with bleeding disorders or stomach ulcers.
Key safety principles
What to watch for
- Bleeding risk, especially gastrointestinal — consider gastroprotection and avoid unnecessary NSAID use.
- Dual antiplatelet therapy markedly increases bleeding risk and should run only for the planned duration.
- Combining with an anticoagulant needs careful specialist balancing.
Key interactions
What to avoid or check alongside
- Combining them with anti-inflammatory painkillers (NSAIDs) increases the risk of stomach bleeding.
- Taking them with anticoagulant blood thinners such as warfarin or DOACs greatly raises bleeding risk.
- Some acid-reducing PPIs may reduce the effect of clopidogrel, so the choice of stomach medicine is considered.
- Other medicines that affect platelets or clotting, including some antidepressants, add to bleeding risk.
- Heavy alcohol use increases the risk of stomach bleeding.
- Certain other medicines can interact with how clopidogrel and ticagrelor are activated or cleared.
Patient & carer advice
- Report black stools, vomiting blood or unusual bruising
- Do not stop before surgery or dental work without advice — stopping early after a stent can be dangerous
- Avoid over-the-counter NSAIDs unless advised
Use with
Related clinical calculators
Dose and risk decisions for this class often depend on renal function, weight or bleeding/stroke risk. These tools help:
Answers
Antiplatelet drugs: frequently asked questions
Why am I taking two of these at once?
After a stent or heart attack, two antiplatelets are often used together for a set period to prevent clots. This raises bleeding risk, so it is usually only for a defined time set by your specialist.
Can I take painkillers with it?
Paracetamol is usually the safer choice. Avoid ibuprofen and similar anti-inflammatory painkillers unless your doctor agrees, as they increase the risk of stomach bleeding.
Can I stop it before surgery?
Never stop on your own. Tell your dentist or surgeon you take an antiplatelet, and they will decide with your cardiology team whether and when to pause it.
Can I drink alcohol with it?
Moderate drinking is usually acceptable, but heavy alcohol use increases the risk of stomach bleeding, so keep within recommended limits.
Is it safe in pregnancy?
Low-dose aspirin is sometimes used in pregnancy for specific reasons under medical advice, but other antiplatelets are generally avoided. Discuss your treatment with your doctor if you are pregnant or planning to be.
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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