Lovenox vs. Heparin for Blood Clots
Key takeaways:
Lovenox (enoxaparin) and heparin are both injectable blood thinners used to prevent and treat blood clots.
Lovenox is injected once or twice a day. Heparin is typically administered 2 or 3 times a day, but it could be given as often as 6 times a day.
Lovenox and heparin are both available as lower-cost generics. GoodRx can help you save over 60% off the average retail price at certain pharmacies.
Table of contents
A blood clot in a vein — also called a deep vein thrombosis (DVT) — is a serious health concern. In some cases, DVTs can travel to the lungs, block a blood vessel, and cause a pulmonary embolism (PE). It’s estimated that up to 100,000 people in the U.S. die from a blood clot every year. So if you experience a DVT, or have a higher risk of developing one, you’ll likely be prescribed a blood thinner to treat or prevent it.
Lovenox (enoxaparin) and heparin are both blood thinners (anticoagulants) that can be used to help prevent and treat DVTs. Both are effective options. But depending on your situation, one may be a better choice for you.
In this article, we’ll talk about how Lovenox and heparin work for blood clots. We’ll also explain the differences in their doses and side effects.
What is Lovenox?
Lovenox is a blood thinner known as a low molecular weight heparin (LMWH). LMWHs are made from heparin. In a laboratory, heparin is chemically changed to become Lovenox. These changes allow Lovenox to have a more predictable and longer-lasting effect in the body.
What conditions is Lovenox approved to treat?
Lovenox is FDA-approved for a few uses:
DVT prevention and treatment
PE treatment
Prevention of complications in people who recently had a heart attack or unstable chest pain (angina)
Treatment of a heart attack
How does Lovenox work to treat or prevent blood clots?
Lovenox blocks certain proteins (clotting factors) in the body that tell the blood to clot. Blocking these proteins helps prevent blood clots from forming. Lovenox doesn’t break up clots that have already formed. Instead, it helps stop those clots from getting bigger and stops new clots from forming. If Lovenox is being used to treat blood clots, it’ll likely be given with other medications that can break up clots.
What is heparin?
Heparin is also a blood thinner. This medication isn’t typically used outside of hospitals. Heparin is less predictable in the body than Lovenox. So you’ll have to have blood tests done while using it.
What conditions is heparin approved to treat?
Heparin is FDA-approved for the following:
DVT prevention and treatment
PE prevention and treatment
Treatment of blood clots caused by atrial fibrillation (AFib)
Clotting prevention during surgery, blood transfusions, or dialysis
Prevention and treatment of blood clots in the arteries
Treatment of disseminated intravascular coagulation (DIC) — a rare condition where blood clots form throughout the body
How does heparin work to treat or prevent blood clots?
Heparin also blocks clotting factors in a similar way to Lovenox. However, heparin more strongly blocks a clotting factor, called thrombin, than Lovenox. Thrombin keeps your other clotting factors working. So as long as thrombin is working, you’ll keep making blood clots. By strongly blocking thrombin, heparin prevents thrombin from sending this message to make more clots.
Like with Lovenox, heparin doesn’t make existing clots smaller. It helps stop them from getting bigger and prevents new clots. You’ll likely be given other medications to help break up clots if you’re using heparin to treat blood clots.
How are Lovenox and heparin dosed and given?
The way these medications are given is different. The biggest difference is that heparin must be given by a healthcare professional. Lovenox can be self-injected.
Lovenox
Lovenox is a subcutaneous injection (given right beneath the skin). It comes as a prefilled syringe. After a healthcare professional shows you how to use Lovenox, you can inject it at home.
The dose of Lovenox depends on why you’re using it. For DVT prevention, a standard dose is 30 mg every 12 hours or 40 mg once a day. For DVT treatment, the dose is based on body weight. Typical doses are 1 mg per kilogram of body weight every 12 hours or 1.5 mg per kilogram of body weight once a day. Doses for other uses vary, so be sure to follow your provider’s instructions.
Heparin
Heparin also comes available as a subcutaneous injection. But it’s more common to receive it directly into a vein (IV). Heparin is given by a healthcare professional. It’s not common to use it outside of a hospital.
Heparin doses vary based on the form you’re receiving and your body weight. Typical doses range between 5,000 units and 20,000 units. Subcutaneous heparin is usually given every 8 to 12 hours. IV heparin may be given every 4 to 6 hours.
You’ll have regular blood tests done while receiving heparin. Your dose may be changed depending on your test results.
How effective are Lovenox and heparin for blood clots?
The effectiveness of Lovenox and heparin depends on why you’re receiving it.
One large study looked at people who received Lovenox or heparin to prevent DVTs after having a stroke. This study found that Lovenox was more effective. But other studies suggest Lovenox and heparin are similarly effective in other situations. This included DVT prevention after surgery and DVT treatment.
These study results may seem confusing. But what they tell us is that both Lovenox and heparin can be effective for DVTs. The choice may come down to why you’re using the medication. Your healthcare provider can explain why they chose one over the other for you.
What are the known side effects of Lovenox and heparin?
Lovenox side effects are similar to heparin side effects. Bleeding, bruising, and injection site reactions are typical. An injection site reaction is pain or redness where the medication was injected.
Below are the risks of common side effects for Lovenox and heparin:
| Side Effect | Lovenox | Heparin |
|---|---|---|
| Anemia (low red blood cells) | 2-16% | 5% |
| Bleeding | 4-13% | 4% |
| Fever | 5-8% | 4% |
| Injection site bleeding | 3-5% | Less than 1% |
| Bruising | 3% | 3% |
| Nausea | 3% | 2% |
| Swelling in the arms or legs | 2-6% | 2-4% |
| Blood in urine | Up to 2% | 2% |
What are the serious side effects of Lovenox and heparin?
Both Lovenox injections and heparin injections also have risks of serious side effects.
Major bleeding can happen with either medication, including brain bleeds. This can be life-threatening. Discuss with your healthcare provider signs of serious bleeding to watch for, especially if you’re using Lovenox at home.
Both Lovenox and heparin can also cause a life-threatening reaction called heparin-induced thrombocytopenia (HIT). This is where the medication causes your body to stop making platelets. While rare, it’s more likely to happen with heparin.
Additionally, Lovenox has a boxed warning (the strictest warning the FDA can give) for spinal and epidural hematomas. This is bleeding in the spinal cord or in the fluid around the spinal cord. While rare, they can cause permanent damage, including paralysis. If you have a history of spine surgeries or injuries, let your healthcare provider know.
What interactions do Lovenox and heparin have?
The most important Lovenox interactions and heparin interactions to be aware of are those that raise your risk of bleeding. Lovenox and heparin can interact with medications that affect how your body makes blood clots.
Examples of medications that affect blood clotting include:
Other blood thinners, including warfarin (Coumadin, Jantoven) and apixaban (Eliquis)
Antiplatelet medications, such as clopidogrel (Plavix)
Nonsteroidal anti-inflammatory drugs (NSAIDS), such as ibuprofen (Advil, Motrin) and aspirin
There are other medications that may interact with Lovenox and heparin. It’s best to provide an updated medication list to your healthcare team before starting either medication. This will help them look for and properly manage medication interactions.
How to save on Lovenox and heparin
There are many ways to save on Lovenox and heparin. Both are available as lower-cost generics. GoodRx can help you navigate many ways to save on your prescription.
Save with GoodRx. GoodRx can help you save over 75% off the average retail price of the generic version of heparin. Generic heparin’s price at certain pharmacies is less than $35 for 60 vials with a free GoodRx discount.
Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for Lovenox’s patient assistance program, which offers the medication free of cost.
The bottom line
Both Lovenox and heparin are used to prevent and treat blood clots in the body. They work similarly, but have some key differences. Lovenox can be used at home, while heparin is usually given in hospitals or infusion centers.
Side effects for both Lovenox and heparin are similar. Bleeding and bruising are most common and usually minor. But there are more serious side effects that can happen with these blood thinners. It’s best to speak with your healthcare provider on which may be the best option for you and before taking any other medications with either.
Why trust our experts?
References
Cardinal Health. (2021). Heparin sodium [package insert].
Cardinal Health. (2022). Enoxaparin sodium [package insert].
Centers for Disease Control and Prevention. (2020). Impact of blood clots on the United States.
Fareed, J., et al. (2011). Differentiation of parenteral anticoagulants in the prevention and treatment of venous thromboembolism. Thrombosis Journal.
Food and Drug Administration. (2018). Generic enoxaparin questions and answers.
Indiana Hemophilia & Thrombosis Center. (n.d.). Antibodies may form with use of heparin.
Jupalli, A., et al. (2022). Enoxaparin. StatPearls.
National Blood Clot Alliance. (n.d.). Low molecular weight heparin (LMWH).
National Heart, Lung, and Blood Institute. (2019). Disseminated intravascular coagulation.
Palta, S., et al. (2014). Overview of the coagulation system. Indian Journal of Anaesthesia.
Sanofi-Aventis LLC. (2006). New study shows LOVENOX® (enoxaparin sodium injection) is more effective than unfractionated heparin (UFH) for lowering the risk of venous thromboembolism (VTE) in patients with acute ischemic stroke.
Warnock, L. B., et al. (2021). Heparin. StatPearls.
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