enoxaparin sodium at a glance
Medicine class
Low molecular weight heparin anticoagulant
Usual role
Preventing and treating blood clots; also used in haemodialysis and some acute coronary syndromes
How it is usually given
A pre-filled syringe injected under the skin; it must not be injected into muscle
Main safety issue
Bleeding, particularly with kidney impairment or other medicines that affect clotting
What is enoxaparin sodium used for?
Selected UK products are licensed in adults for:
Preventing venous thromboembolism in surgical patients at moderate or high risk
Preventing venous thromboembolism during acute illness with reduced mobility and increased clot risk
Treating deep-vein thrombosis and pulmonary embolism, except pulmonary embolism likely to require thrombolysis or surgery
Extended treatment and recurrence prevention of venous thromboembolism in active cancer
Preventing clots in the extracorporeal circuit during haemodialysis
Treating unstable angina or non-ST-elevation myocardial infarction alongside aspirin
Treating acute ST-elevation myocardial infarction
How does enoxaparin sodium work?
Enoxaparin enhances antithrombin activity and mainly inhibits clotting factor Xa, with a smaller effect on thrombin. This reduces fibrin formation, making new clots less likely and limiting extension of an existing clot; it does not directly dissolve a clot.
How to take enoxaparin sodium
Use the supplied pre-filled syringe exactly as demonstrated by a healthcare professional and follow the leaflet for that brand and device.
Inject into a pinched fold of fatty tissue under the skin, usually on alternating sides of the abdomen.
Do not inject into muscle, bruised skin, scars or inflamed areas.
Do not expel the intentional air bubble unless specifically instructed for your product.
Keep the skin fold held until the injection is complete and do not rub afterwards.
Activate the needle-safety device where fitted and place the syringe immediately in a sharps bin.
Store as directed and do not freeze.
enoxaparin sodium side effects
Common or expected effects
- Bruising or bleeding more readily than usual
- Pain, redness, swelling, a small lump or haematoma at the injection site
- Itching, hives or other mild skin reactions
- Headache
- Changes in platelet counts
- Raised liver enzymes detected by blood tests
Get urgent medical advice
- Major or internal bleeding
- Immune-mediated heparin-induced thrombocytopenia, potentially with new clots
- Severe allergic reaction
- Spinal or epidural haematoma causing back pain, weakness, numbness or bladder or bowel dysfunction
- Painful purple skin lesions, skin death or a widespread pustular rash
enoxaparin sodium in pregnancy
Low molecular weight heparin does not cross the placenta and is commonly used when anticoagulation is needed during pregnancy. Prescribing requires assessment of clinical need and bleeding risk. Labour, caesarean birth and spinal or epidural anaesthesia require a coordinated plan. Pregnant patients with mechanical prosthetic heart valves need specialist management.
enoxaparin sodium while breastfeeding
Enoxaparin can be used during breastfeeding. Transfer into milk is expected to be negligible and absorption by the infant is unlikely. As a precaution, watch a full-term healthy infant for unusual bruising or bleeding; seek specialist advice if the infant is premature or unwell.
enoxaparin sodium interactions
Medicines that increase bleeding or potassium require review. Do not stop prescribed antiplatelet or anticoagulant treatment without clinical advice.
NSAIDs and anti-inflammatory-dose aspirin
Ibuprofen, naproxen, diclofenac, ketorolac and similar medicines can increase bleeding risk.
Other anticoagulants or thrombolytics
Combined effects can substantially increase bleeding risk and require planned monitoring or switching.
Antiplatelet medicines
Aspirin, clopidogrel and related medicines increase bleeding risk, although combinations may be intentionally prescribed in acute coronary syndromes.
Common questions about enoxaparin sodium
Answers are fully visible for fast scanning and source review.
Is enoxaparin sodium a blood thinner?
Yes. It is an anticoagulant that reduces the blood’s ability to form or enlarge clots; it does not make blood physically thinner.
Does it dissolve an existing blood clot?
No. It limits further clot formation and extension, allowing the body’s own processes to break the clot down over time.
Should I remove the syringe’s air bubble?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.