Enoxaparin: Indications, Dosing & Side Effects

Key points
  • Enoxaparin is an injectable blood thinner used to help prevent or treat dangerous clots, including DVT and clot-related lung complications, especially after surgery or during limited mobility.
  • Dosing depends on the condition being treated and may range from once-daily prevention to weight-based treatment schedules, including use during hemodialysis and some heart conditions.
  • Seek urgent medical care for bleeding that won’t stop, coughing or vomiting blood, blood in urine or stool, or sudden stroke-like symptoms such as one-sided weakness, trouble speaking, or vision changes.

Enoxaparin is an injectable anticoagulant used to prevent the formation of blood clots in the veins and arteries. It is commonly prescribed for people who have undergone surgery, have limited mobility, or are receiving hemodialysis. This medication is also used in the treatment of certain heart conditions, such as acute myocardial infarction (heart attack) and unstable angina.

Enoxaparin (Lovenox) is available in pharmacies and drugstores as a prefilled injection pen containing 20, 40, 60, 80, or 100 mg of enoxaparin sodium.

The medication can be administered as a subcutaneous injection into the abdominal area or as an intravenous injection given by a nurse in a hospital setting under medical supervision. The exact dose and method of administration must always be determined by a healthcare provider.

subcutaneous injection into the abdomen

Indications for use

Enoxaparin sodium is indicated for the treatment or prevention of the following conditions:

  • Deep vein thrombosis, with or without pulmonary embolism;

  • Unstable angina;

  • Myocardial infarction (heart attack);

  • Venous thromboembolism associated with orthopedic or general surgery;

  • Venous thromboembolism in bed bound patients due to heart failure, respiratory failure, severe infections, or rheumatic conditions.

Enoxaparin is also indicated to prevent clot formation in extracorporeal circulation during hemodialysis in people with kidney disease. 

People who are currently or recently hospitalized or recovering from surgery are at increased risk of developing venous thromboembolism, according to the Centers for Disease Control and Prevention (CDC).

How to use

Enoxaparin sodium is usually administered subcutaneously, injected under the skin of the abdomen. The injection can be given by the person themselves or by a healthcare professional, depending on medical guidance.

Also recommended: Subcutaneous Injection: Instructions & Recommendations tuasaude.com/en/subcutaneous-injection

In some cases, enoxaparin may be administered directly into a vein, which should only be done by a nurse in a hospital setting under medical supervision.

When using subcutaneous injections, it is important to alternate between the left and right sides of the abdomen with each dose to reduce local irritation.

Dosing instructions

The recommended adult dose of enoxaparin varies based on whether it is used for prevention or treatment of blood clots, as well as the person’s age and health history.

Indication Dosage
Prevention of venous thromboembolism before surgery

People with moderate risk: the recommended dose is 20 mg or 40 mg once daily, administered subcutaneously. For general surgery, the first dose is usually given 2 hours before the procedure. Treatment typically lasts 7 to 10 days or as directed by a doctor.

People with high risk: the recommended dose is 40 mg once daily, administered subcutaneously starting 12 hours before surgery, or 30 mg twice daily starting 12 to 24 hours after surgery. Treatment usually lasts 4 to 5 weeks, according to medical guidance.

Prevention of venous thromboembolism in medical patients The recommended dose is 40 mg once daily, administered subcutaneously. Treatment should last at least 6 days and continue until the person regains full mobility, for a maximum of 14 days.
Prevention of clot formation during hemodialysis The recommended dose is 0.5 to 1.0 mg per kilogram of body weight. This dose is calculated by the doctor and administered into the arterial line of the extracorporeal circulation circuit during hemodialysis.
Treatment of unstable angina and myocardial infarction without ST-segment elevation The recommended dose is 1 mg per kilogram of body weight, administered subcutaneously every 12 hours. This treatment is used in combination with aspirin at doses of 100 to 325 mg once daily. Treatment usually lasts 2 to 8 days, depending on medical guidance.
Treatment of acute myocardial infarction with ST-segment elevation The recommended regimen includes an initial 30 mg dose administered intravenously in the hospital, followed by 1 mg per kilogram of body weight administered subcutaneously. This is then continued with 1 mg/kg subcutaneously every 12 hours.

Subcutaneous enoxaparin is supplied in single-use prefilled pens containing 20, 40, 60, 80, or 100 mg of injectable solution and should be discarded after use.

Side effects

Common side effects of enoxaparin include nausea, diarrhea, anemia, mental confusion, and pain, redness, swelling, or irritation at the injection site.

More serious side effects require immediate medical attention and include bleeding that does not stop, easy bruising, nosebleeds, bleeding gums, vaginal bleeding, blood in the urine or stool, coughing up blood, or vomiting blood.

Enoxaparin may also increase the risk of bleeding in the brain and stroke. Emergency medical care should be sought if symptoms such as sudden weakness, numbness or tingling on one side of the body, difficulty speaking, partial vision loss, blurred vision, or shortness of breath occur, according to the CDC.

Also recommended: Top 12 Stroke Symptoms (You Should Not Ignore) tuasaude.com/en/stroke-symptoms

Contraindications for use

Enoxaparin sodium should not be used by people with active bleeding, a history of stroke, or a history of heparin-induced thrombocytopenia (low platelets).

It should also not be used by anyone with a known allergy to any component of the medication.

The safety and effectiveness of enoxaparin in pediatric patients have not been established, and enoxaparin is not approved for use in neonates or infants. Use in children should only occur under specialist guidance when prescribed.

The benefits of breastfeeding should be weighed against the clinical need for enoxaparin and any potential risks to the breastfed child, in consultation with a healthcare provider.