Lovenox Is an Injectable Blood Thinner Used to Prevent and Treat Blood Clots

Lovenox (Enoxaparin Sodium) is a prescription injectable blood thinner that belongs to a class of drugs called low molecular weight heparins (LMWHs). It works by preventing the formation of blood clots in your veins and arteries, and it's one of the most widely prescribed anticoagulants in the world.

Whether you've just been prescribed Lovenox or you're researching it for someone you care about, this guide covers everything you need to know — from what it treats to how much it costs in 2026.

What Is Lovenox?

Lovenox is the brand name for Enoxaparin Sodium, manufactured by Sanofi-Aventis. It's classified as a low molecular weight heparin — a type of blood thinner derived from standard heparin but engineered to be more predictable and easier to use.

Unlike older blood thinners like Warfarin (which you take as a pill), Lovenox is given as a subcutaneous injection — a shot just under the skin. It comes in prefilled syringes, making it practical for patients to use at home after a brief training session.

A generic version, simply called Enoxaparin, is available and works the same way at a lower cost.

To understand how Lovenox works at a deeper level, read our guide on how Lovenox works: mechanism of action explained.

What Is Lovenox Used For?

Lovenox is FDA-approved for several important uses:

Preventing Blood Clots After Surgery

One of the most common uses. After hip replacement, knee replacement, or abdominal surgery, patients are at high risk for developing deep vein thrombosis (DVT) — a blood clot in a deep vein, usually in the leg. Lovenox is given to prevent this.

Treating Deep Vein Thrombosis (DVT)

If you've already developed a DVT, Lovenox is used to treat it and prevent the clot from growing or breaking off and traveling to your lungs (pulmonary embolism). It can be used in the hospital or at home for outpatient treatment.

Heart Attack Treatment

Lovenox is used during and after certain types of heart attacks — specifically unstable angina, non-Q-wave myocardial infarction, and acute ST-segment elevation myocardial infarction (STEMI). It's often given alongside Aspirin.

Off-Label Uses

Doctors also commonly prescribe Lovenox for:

• Bridge therapy — temporarily replacing Warfarin before and after surgery
• Pregnancy — Lovenox is a preferred blood thinner during pregnancy because it doesn't cross the placenta the way Warfarin does
• Cancer patients — who have elevated blood clot risk from their disease and treatments
• Hospitalized medical patients — for clot prevention during extended bed rest

How Is Lovenox Taken?

Lovenox is injected under the skin (subcutaneously), usually in the fatty tissue of your abdomen — at least two inches away from your belly button.

Key points about taking Lovenox:

• It comes in prefilled syringes in doses ranging from 30 mg to 150 mg
• A multi-dose vial (300 mg/3 mL) is also available for healthcare facilities
• Do not expel the air bubble from the prefilled syringe before injecting — the air bubble helps push all the medication out and reduces bruising
• Rotate injection sites to avoid irritation — alternate between the left and right sides of your abdomen
• Your nurse or pharmacist will teach you how to self-inject before you start home treatment

Typical dosing:

• DVT prevention: 30 mg every 12 hours or 40 mg once daily
• DVT/PE treatment: 1 mg/kg every 12 hours or 1.5 mg/kg once daily
• Heart attack: 30 mg IV bolus followed by 1 mg/kg subcutaneously, then 1 mg/kg every 12 hours

Your exact dose depends on your weight, kidney function, and the condition being treated. Never adjust your dose without talking to your doctor.

Who Should Not Take Lovenox?

Lovenox is not safe for everyone. You should not take it if you have:

• Active major bleeding — such as a bleeding ulcer or hemorrhagic stroke
• History of heparin-induced thrombocytopenia (HIT) — a dangerous immune reaction to heparin-based drugs
• Allergy to Enoxaparin, heparin, or pork products — Lovenox is derived from porcine (pig) intestinal tissue
• Allergy to benzyl alcohol — the multi-dose vial contains this preservative

Use with caution if you have:

• Kidney disease (dose adjustment is needed if creatinine clearance is below 30 mL/min)
• Low body weight (under 45 kg / 99 lbs) — higher risk of bleeding
• A history of bleeding disorders
• Upcoming spinal or epidural procedures — there's a serious risk of spinal hematoma

Always tell your doctor about all medications you're taking, including over-the-counter drugs and supplements. See our Lovenox drug interactions guide for details.

How Much Does Lovenox Cost?

Cost varies widely depending on whether you use brand-name Lovenox or generic Enoxaparin:

• Brand Lovenox: $50–$600+ per month depending on dose and quantity
• Generic Enoxaparin: approximately $30–$150 for a 30-day supply of prefilled syringes
• Discount prices: GoodRx and similar tools show prices as low as $25–$80 for common generic doses

Insurance coverage: Most insurance plans and Medicare cover generic Enoxaparin. Brand-name Lovenox may require prior authorization. Medicare Part B covers it when administered by a healthcare provider; Part D covers self-administered doses.

For tips on reducing your cost, read our guide on how to save money on Lovenox.

If you're a provider looking to help patients with costs, see our provider's guide to helping patients save on Lovenox.

Final Thoughts

Lovenox is a proven, widely-used blood thinner that plays a critical role in preventing and treating dangerous blood clots. Whether you're recovering from surgery, managing a clotting disorder, or going through pregnancy, understanding your medication helps you use it safely and effectively.

If you're having trouble finding Lovenox at your pharmacy, use Medfinder to check real-time stock near you — no phone calls needed.