Lovenox vs. heparin: Differences, similarities, and which is better for you

Drug overview & main differences | Conditions treated | Efficacy | Insurance coverage and cost comparison | Side effects | Drug interactions | Warnings | FAQ

You may be prescribed Lovenox (enoxaparin) or heparin to treat or prevent a blood clot. Lovenox and heparin are both injectable drugs that are part of a larger group of medications called anticoagulants. As anticoagulants, or blood thinners, Lovenox and heparin help treat and prevent deep vein thrombosis (DVT) and pulmonary embolism (PE).

Both Lovenox and heparin have a similar mechanism of action. They work by binding to a small protein molecule called antithrombin and blocking the actions of thrombin, factor Xa, and other enzymes involved in blood clotting. Lovenox is classified as a low molecular weight heparin (LMWH) and is not the same as standard heparin. 

What are the main differences between Lovenox and Heparin?

Lovenox is the brand name for enoxaparin. It is a low molecular weight heparin manufactured by Sanofi-Aventis. Lovenox can be injected intravenously (through a vein) or subcutaneously (under the skin), and it is available in various forms and strengths, including a 30 mg/0.3 mL, 40 mg/0.4 mL, 60 mg/0.6 mL, 80 mg/0.8 mL, and 100 mg/1 mL single-dose prefilled syringe. Lovenox is also available as a 300 mg/3 mL multiple-dose vial.

Lovenox has a half-life of around 4.5 to 7 hours after administration, and its anticoagulant effects last up to 12 hours. Because of its long half-life and predictable effects, Lovenox does not need extensive monitoring or supervision to use it.

Heparin, also known as standard heparin or unfractionated heparin (UFH), is a generic anticoagulant injection. Heparin also goes by brand names such as Hep-Lock. 

Heparin is usually administered intravenously or subcutaneously. It is available in single-dose and multiple-dose forms with varying strengths that may include 1,000 USP units/mL, 5,000 USP units/mL, and 10,000 USP units/mL.

Compared to Lovenox, heparin has a shorter half-life of around one hour and 30 minutes. Heparin needs to be given more often than Lovenox, and it’s usually administered in a hospital setting. The anticoagulant effects of heparin need to be monitored because its effects are more unpredictable than low molecular weight heparin. 

Main differences between Lovenox and Heparin
	Lovenox	Heparin
Drug class	Anticoagulant	Anticoagulant
Brand/generic status	Brand and generic version available	Brand and generic version available
What is the brand and generic name?	Brand name: Lovenox Generic name: Enoxaparin	Brand name: Heparin Sodium ADD-Vantage Generic name: Heparin
What form(s) does the drug come in?	Solution for injection	Solution for injection
What is the standard dosage?	40 mg subcutaneously once daily Dosage may vary depending on the condition being treated.	5000 units subcutaneously every eight to 12 hours Dosage may vary depending on the condition being treated.
How long is the typical treatment?	Seven days, more or less, depending on the condition being treated.	Seven days, more or less, depending on the condition being treated.
Who typically uses the medication?	Adults, children, and infants	Adults, children, and infants

Conditions treated by Lovenox and Heparin

Both Lovenox and heparin are approved in the United States for the treatment of venous thromboembolism (VTE), a condition characterized by clots that form in the blood vessels. Blood clots can often form in a deep vein of the legs or arms (deep vein thrombosis/DVT) and travel to the lungs where they become lodged in an artery (pulmonary embolism/PE).

Lovenox and heparin are also used for the prevention of blood clots, especially after a surgery such as knee surgery or hip replacement surgery. Bed rest after a surgery is one of the biggest risk factors for blood clots. Other risk factors for blood clots include a family history of blood-clotting disorders, pregnancy, obesity, smoking, and cancer.

Heparin is also approved to reduce the risk of blood clots that may occur with atrial fibrillation, blood transfusion, and dialysis procedures. Conversely, Lovenox is also approved to treat and prevent complications in people who experience certain types of chest pain (unstable angina) and heart attacks (non-Q-wave myocardial infarction). 

Conditions treated by Lovenox and Heparin
Condition	Lovenox	Heparin
Treatment and prevention of venous thromboembolism	Yes	Yes
Treatment and prevention of blood clots after surgery	Yes	Yes
Prevention and treatment of complications from atrial fibrillation	Off-label	Yes
Prevention of complications from unstable angina and heart attacks	Yes	Off-label

Is Lovenox or Heparin more effective?

Lovenox and heparin are both effective for treating and preventing blood clots. They work in similar ways to allow blood to flow more freely. Preference for one drug over the other depends on cost, side effects, and administration.

Compared to heparin, Lovenox has a longer half-life. Meaning, it lasts longer and can be administered once daily. Dosing is more predictable with Lovenox, although patients with a high body weight need more frequent dosing, such as one injection two times daily. 

In a meta-analysis from the Journal of Thrombosis and Haemostasis, enoxaparin and unfractionated heparin were compared for preventing blood clots in hospitalized patients. Four clinical trials were included in the meta-analysis and evaluated a total of 3,600 patients. Results found that, compared to heparin, enoxaparin significantly reduced blood clots without increasing the risk of major bleeding.

One caveat to using Lovenox is that its dosage needs to be adjusted in patients with renal failure. Otherwise, there is an increased risk of bleeding. In clinical practice, unfractionated heparin is preferred for people with kidney impairment. 

Your doctor will prescribe the best anticoagulant for your condition. The most effective anticoagulant will be determined based on your overall medical history. 

Coverage and cost comparison of Lovenox vs. Heparin

Most Medicare and insurance plans will cover Lovenox. However, insurance is more likely to cover generic Lovenox, and it might not cover the full cost. The average retail price of Lovenox is around $380. If you’re purchasing Lovenox injections for home use from the pharmacy, you can use a Lovenox SingleCare card to save money. Instead of paying full price for Lovenox, you could pay less than $75 for 10 generic prefilled syringes. 

Heparin is usually covered by Medicare and insurance plans. It also tends to be less expensive than Lovenox. Still, the average retail price of heparin is $120, depending on the quantity and dosage. While heparin is typically administered by a healthcare professional, you may be able to administer heparin at home with guidance from a healthcare provider. With a SingleCare heparin coupon, you may be able to fill your prescription for less than $50 at participating pharmacies. 

Cost comparison and coverage of Lovenox vs. Heparin
	Lovenox	Heparin
Typically covered by insurance?	Yes	Yes
Typically covered by Medicare Part D?	Yes	Yes
Standard dosage	40 mg subcutaneously once daily (quantity of 10)	5000 units subcutaneously every eight to 12 hours (quantity of 10)
Typical Medicare copay	$5–$58	$1–$3
SingleCare cost	$71+	$45+

Get a SingleCare pharmacy discount card

Common side effects of Lovenox vs. Heparin

The most common side effect of Lovenox and heparin is injection site reactions. After administering Lovenox or heparin injections, you may experience pain, discomfort, irritation, or swelling around the area of injection. However, these side effects tend to be mild and go away on their own.

Since Lovenox and heparin prevent blood clots, they may cause bleeding side effects. While using Lovenox or heparin, you may experience more frequent bruising. Anticoagulants can also cause severe bleeding. Signs of severe bleeding include heavy bruising and blood in the stool or urine. Seek medical attention if you experience signs of severe bleeding. 

See the chart below for other common side effects. 

Lovenox vs. Heparin common side effects
	Lovenox		Heparin
Side Effect	Applicable?	Frequency	Applicable?	Frequency
Pain, irritation, swelling around the injection site	Yes	*	Yes	*
Bleeding	Yes	*	Yes	*
Elevated liver enzymes	Yes	*	Yes	*
Nausea	Yes	*	No	–
Diarrhea	Yes	*	No	–

*not reported

Frequency is not based on data from a head-to-head trial. This may not be a complete list of adverse effects that can occur. Please refer to your doctor or healthcare provider to learn more.

Source: DailyMed (Lovenox), DailyMed (Heparin)

Drug interactions of Lovenox vs. Heparin

Lovenox and heparin have similar drug interactions. Platelet inhibitors, or antiplatelet agents, are a different class of drugs that can also help prevent blood clots. Combining antiplatelets like clopidogrel, ticagrelor, or prasugrel with Lovenox or heparin can increase the risk of bleeding.

Nonsteroidal anti-inflammatory drugs (NSAIDs) can affect the function of platelets. The risk of bleeding may be increased when taking NSAIDs together with Lovenox or heparin. Tell your doctor if you’re taking NSAIDs before starting treatment on Lovenox or heparin.

Lovenox vs. Heparin drug interactions
Drug	Drug Class	Lovenox	Heparin
Aspirin Ibuprofen Indomethacin Celecoxib	Nonsteroidal anti-inflammatory drugs (NSAIDs)	Yes	Yes
Clopidogrel Ticagrelor Prasugrel Dipyridamole	Antiplatelet agents	Yes	Yes

Consult a healthcare professional for other possible drug interactions

Warnings of Lovenox and Heparin

Anticoagulants like Lovenox and heparin can increase the risk of major bleeding, or hemorrhage. Bleeding can be severe and is often indicated by signs such as blood in the urine or stool. The risk of bleeding may also be higher in people with a history of bleeding disorders. 

Heparin can cause heparin-induced thrombocytopenia (HIT), a serious condition characterized by a low platelet count. While people don’t usually experience clear symptoms of HIT, it is a potentially life-threatening complication that can result in severe bleeding or death. Compared to Lovenox, heparin has a higher risk of HIT. Heparin use is often monitored more closely for this reason. 

Lovenox carries an increased risk of spinal epidural hematoma, or a collection of blood around the spinal cord. A spinal epidural hematoma can lead to complications or paralysis. The risk is increased if you’ve had a past or recurring spinal or epidural puncture; you’re taking NSAIDs, platelet inhibitors, or anticoagulants; or you have an indwelling epidural catheter.

Consult your healthcare provider for other precautions associated with Lovenox and heparin.

Frequently asked questions about Lovenox vs. Heparin

What is Lovenox?

Lovenox is an injectable anticoagulant, or blood thinner. It is also classified as a low molecular weight heparin. Lovenox is available in various strengths as a prefilled syringe or multiple-dose vial. It is usually administered once or twice daily as a subcutaneous injection. The generic version of Lovenox is enoxaparin. 

What is Heparin?

Heparin is also known as standard or unfractionated heparin. It is available in generic or brand-name versions. Heparin is administered as an intravenous or subcutaneous injection. It is usually given in a hospital setting, although some forms of heparin can be administered at home. 

Are Lovenox and Heparin the same?

Lovenox and heparin are not the same. Lovenox is a low molecular weight heparin (LMWH), which is different from standard or unfractionated heparin (UFH). Although Lovenox and heparin are both anticoagulants, they have differences in formulation and FDA-approved uses. 

Is Lovenox or Heparin better?

Lovenox and heparin are both effective for treating and preventing blood-clotting conditions like deep vein thrombosis (DVT) and pulmonary embolism (PE). Lovenox has more predictable dosing and monitoring parameters; thus, it’s preferred over heparin for home use. The long half-life of Lovenox means it can be dosed once daily. 

Compared to Lovenox, heparin needs to be dosed more frequently and at higher doses because of its short half-life. Heparin is less expensive than Lovenox, and it’s usually administered in a hospital setting where monitoring for adverse effects is easier. 

Can I use Lovenox or Heparin while pregnant?

Lovenox and heparin are generally safe and effective for treating thromboembolic disorders during pregnancy. Both anticoagulants do not cross the placenta. However, low molecular weight heparins (LMWHs), like Lovenox, are preferred for treating blood clots in pregnant women. 

Can I use Lovenox or Heparin with alcohol?

Healthcare providers recommend limiting or avoiding alcohol while using Lovenox or heparin. Alcohol can act as a blood thinner, which may lead to an increased risk of bleeding when alcohol is combined with an anticoagulant drug. 

What can be used instead of heparin?

Low molecular weight heparins (LMWHs) are often used instead of heparin. Lovenox (enoxaparin), Fragmin (dalteparin), and Innohep (tinzaparin) are examples of LMWHs that can be used to treat or prevent blood clots. Arixtra (fondaparinux) is another antithrombotic agent, different from LMWH and UFH, that can inhibit factor Xa and treat blood clots. 

Direct oral anticoagulants (DOACs), which come in pill form, are also widely used instead of heparin. Examples of DOACs include Xarelto (rivaroxaban), Pradaxa (dabigatran), and Eliquis (apixaban). 

What is Lovenox used for?

Lovenox (enoxaparin) is used for anticoagulation and thromboprophylaxis. It can help treat or prevent blood clots that could form in blood vessels. Lovenox can help treat blood clots that form in the legs or arms (deep vein thrombosis) or clots that become lodged in the lungs (pulmonary embolism). Lovenox is also useful for preventing complications from unstable angina and certain types of heart attacks. 

Is Lovenox a high-risk medication?

Lovenox is a high-risk, or high-alert medication. Although it is generally a safe medication, Lovenox can cause serious injury and complications if used incorrectly. High doses of Lovenox may also cause an increased risk of bleeding and adverse effects. Lovenox should only be used with a prescription under the guidance of a healthcare provider.