Enoxaparin

Question 1

Drug class?

Answer 1

Heparins

Question 2

How does it work?

Answer 2

Enoxaparin is a low molecular weight heparin. Enoxaparin sodium is characterised by a higher ratio of antithrombotic activity to anticoagulant activity than unfractionated heparin. At recommended doses, it does not significantly influence platelet aggregation, binding of fibrinogen to platelets or global blood clotting tests such as APTT and prothrombin time.

Enoxaparin binds to anti-thrombin III leading to inhibition of coagulation factors IIa and Xa.

Enoxaparin has been shown to increase the blood concentration of Tissue Factor Pathway Inhibitor.

Question 3

Indications?

Answer 3

• Prophylaxis of thromboembolic disorders of venous origin, in particular those which may be associated with orthopaedic or general surgery.
• Treatment of venous thromboembolic disease presenting with deep vein thrombosis, pulmonary embolism or both.
• Treatment of unstable angina and non-Q-wave myocardial infarction, administered concurrently with aspirin.
• Treatment of acute ST-segment Elevation Myocardial Infarction (STEMI) including patients to be managed medically or with subsequent Percutaneous Coronary Intervention (PCI) in conjunction with thrombolytic drugs (fibrin or non-fibrin specific).

Question 4

Contra-indications?

Answer 4

• Contraindicated in patients with:
• Acute bacterial endocarditis
• Active major bleeding and conditions with a high risk of uncontrolled haemorrhage, including recent haemorrhagic stroke
• Thrombocytopenia in patients with a positive in-vitro aggregation test in the presence of enoxaparin;
• Active gastric or duodenal ulceration
• Hypersensitivity to either enoxaparin sodium, heparin or its derivatives including other Low Molecular Weight Heparins, hypersensitivity to benzyl alcohol
• In patients receiving heparin for treatment rather than prophylaxis, locoregional anaesthesia in elective surgical procedures is contra-indicated.

Question 5

Side effects?

Answer 5

• Haemorrhages are the most commonly reported adverse effect.

Question 6

Possible interactions?

Answer 6

• It is recommended that agents which affect haemostasis should be discontinued prior to enoxaparin therapy unless their use is essential