What is Enoxaparin used for?

treating blood clots in the legs or lungs; preventing clots after surgery; preventing clots in people in the hospital for a serious illness; some heart problems, like certain heart attacks and chest pain.

What are the common side effects of Enoxaparin?

Bruising more easily. Small bleeding, like from your gums or nose. Heavier periods. Bruising, pain, or a small lump where the shot goes in. Low red blood cells, which can make you tired.

When should I call my care team while taking Enoxaparin?

Bleeding that will not stop, such as a nosebleed or a cut that keeps bleeding; Red, pink, or dark brown urine; Red or black stools that look like tar; Coughing up blood, or throwing up blood or something that looks like coffee grounds; A sudden bad headache, confusion, or weakness; Numbness, tingling, or weakness in your legs, or trouble controlling your bladder or bowels.

Enoxaparin

Say it: ee-nox-uh-PAIR-in · Brand names: Lovenox

Enoxaparin is a blood thinner shot that helps prevent and treat harmful blood clots.

What it is

Enoxaparin is a type of heparin. It helps a natural protein in your blood slow down clotting. This makes it harder for dangerous clots to form or grow.

Often used for

treating blood clots in the legs or lungs
preventing clots after surgery
preventing clots in people in the hospital for a serious illness
some heart problems, like certain heart attacks and chest pain

How you get it

It is a shot given just under the skin, usually in the belly. Most people get it once or twice a day. You or a family member can learn to give it at home. Your schedule may be different.

Common side effects and what helps

Bruising more easily. Use a soft toothbrush and an electric razor.
Small bleeding, like from your gums or nose. Press firmly for 10 minutes. Call if it does not stop.
Heavier periods. Tell your team if your periods change.
Bruising, pain, or a small lump where the shot goes in. Change spots each time and do not rub after the shot.
Low red blood cells, which can make you tired. Your team will check your blood.

Call your care team right away if you have

Bleeding that will not stop, such as a nosebleed or a cut that keeps bleeding
Red, pink, or dark brown urine
Red or black stools that look like tar
Coughing up blood, or throwing up blood or something that looks like coffee grounds
A sudden bad headache, confusion, or weakness
Numbness, tingling, or weakness in your legs, or trouble controlling your bladder or bowels

Before you start, tell your team

If you have ever had a low platelet count from heparin (heparin-induced thrombocytopenia)
If you are allergic to heparin or pork products
If you have kidney problems
All medicines, vitamins, and herbs you take, especially aspirin, ibuprofen, naproxen, and other blood thinners
If you are pregnant, may become pregnant, or are breastfeeding
If you have a surgery, procedure, or spinal tap planned

Good to know

If you get a spinal tap or a numbing shot in the back (epidural), there is a rare risk of bleeding near the spine that can cause lasting weakness. Tell your team you take this medicine.
Rarely, it can cause a drop in platelets, the cells that help blood clot. You will have blood tests to check your platelet count.
If your kidneys do not work well, your team may change your dose.
It cannot be swapped one for one with other heparin medicines.

At home

Your team will show you how to give the shot. Use the belly, at least 2 inches from your belly button, and switch sides each time.
Pinch a fold of skin and push the needle straight in. Do not push out the small air bubble in a prefilled syringe.
Do not rub the spot after the shot. This helps prevent bruising.
Put used needles in a hard sharps container. Never reuse a needle.
Store at room temperature. If you miss a dose, ask your team what to do.

Questions to ask

Who will teach me to give the shot?
How long will I need these shots?
How will we check my platelet count?
Where do I get a sharps container and how do I throw it away?

Side effect guides

Sources

Quick answers

What is Enoxaparin?: Enoxaparin is a blood thinner shot that helps prevent and treat harmful blood clots. Brand names: Lovenox.
What is Enoxaparin used for?: treating blood clots in the legs or lungs; preventing clots after surgery; preventing clots in people in the hospital for a serious illness; some heart problems, like certain heart attacks and chest pain.
How is Enoxaparin given?: It is a shot given just under the skin, usually in the belly. Most people get it once or twice a day. You or a family member can learn to give it at home. Your schedule may be different.
What are the common side effects of Enoxaparin?: Bruising more easily. Small bleeding, like from your gums or nose. Heavier periods. Bruising, pain, or a small lump where the shot goes in. Low red blood cells, which can make you tired.
When should I call my care team while taking Enoxaparin?: Bleeding that will not stop, such as a nosebleed or a cut that keeps bleeding; Red, pink, or dark brown urine; Red or black stools that look like tar; Coughing up blood, or throwing up blood or something that looks like coffee grounds; A sudden bad headache, confusion, or weakness; Numbness, tingling, or weakness in your legs, or trouble controlling your bladder or bowels.

Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.