What is enoxaparin?

Enoxaparin (also known as Lovenox® or low molecular weight heparin) is a blood thinner (anticoagulant). It is used to treat patients who have a blood clot. It can also be used to prevent blood clots in patients who are at risk of developing one.

It is available in prefilled syringes of 30-mg, 40-mg, 60-mg, 80-mg, 100-mg, 120-mg, and 150-mg strengths. For smaller doses, a 100mg/ml multi-dose vial is available. It is a colorless to pale yellow liquid that is injected under the skin.


This medicine is offered in many strengths. Always check to be sure that you receive the same strength of medicine each time you pick up a new supply.

If the strength is different, the amount of medicine you need to take will also change.

If you receive a different strength of enoxaparin and this change has not been discussed with you, call your pharmacist.

Storing enoxaparin

  • Store enoxaparin at room temperature or in the refrigerator.
  • Do not freeze the syringe.
  • Use the syringe only one time. Throw away the syringe and needle in a closed container. See “Do You Know… Throwing away sharp objects safely. ”
  • Throw away any unused medicine after the expiration date.
  • If you are using the enoxaparin vial, the vial should be thrown away 28 days from the first day it was used.

Possible side effects of enoxaparin


  • Pain, bruising, bleeding, swelling, or rash at the injection site


  • Nausea
  • Skin rash, itching
  • Unusual bruising or bleeding – bleeding gums, red spots on skin, nose bleeds
  • Heavy menstrual bleeding
  • Blood in urine, coughing up blood
  • Black, tarry stools
  • Problems breathing
  • Feeling dizzy, fainting spells

These are the most common side effects, but there may be others. Please report all side effects to the doctor or nurse.

In case of a severe side effect or reaction, call your doctor, nurse, or pharmacist at 901-595-3300. If you are outside the Memphis area, dial toll-free 1-866-2STJUDE (1-866-278-5833), and press 0 once the call is connected.

Special instructions for enoxaparin

  • About 4 hours after you receive enoxaparin, the staff will take blood samples to measure the level of anti-clotting activity in your blood. Please let the staff know if it has been more than 6 hours after enoxaparin was given. All blood level tests for this drug must be done with blood samples taken from a vein rather than from your central venous line. The nurse may call this a “fresh stick.” While we prefer not to stick you with another needle, it is needed to ensure your health and safety while taking this drug.
  • While you are taking enoxaparin, tell your doctor right away if you have any of these symptoms: trouble breathing, chest pain, feeling dizzy or short of breath, swelling in the legs or arms, severe stomach pain, vision problems, pain when walking, or pain and warmth in your arms or legs.
  • Check your skin closely for easy bruising or red spots, which may mean that you are bleeding. If you notice any bleeding, tell your doctor right away so your enoxaparin dose can be lowered.
  • If you need to have surgery or dental work, tell your surgeon or dentist that you are taking this medicine.
  • This medicine should not be taken on the day of a procedure or surgery and should be withheld 12 to 48 hours before and after, depending upon the type of procedure or surgery. Types of procedures and surgeries include central line placement, lumbar puncture, root canals, and major surgeries like removal of tumors. Please consult your doctor, nurse practitioner, or pharmacist if you have questions about when to stop taking this medicine.
  • Be careful to avoid injury while you are taking enoxaparin. The risk of heavy bleeding is increased even for routine activities like shaving and brushing or flossing your teeth.
  • In case of emergency, carry a card that says you are receiving a blood thinner known as enoxaparin.
  • Do not take the following medicines while you are taking enoxaparin (unless your doctor tells you to do so): warfarin, aspirin, and aspirin-like medicines such as ibuprofen or naproxen.

How to give enoxaparin

Enoxaparin is given as an injection (shot) into the skin. This injection (shot) is given into fatty areas of the body called injection sites. Depending on the size of your child, enoxaparin may be dispensed as a prefilled syringe or as a vial. If you receive a vial, you will fill the syringe yourself before giving the shot.

Injection sites

Choosing an injection site

  • The usual sites are:
    • Abdomen (except for navel and waistline)
    • Upper thighs (small children and infants)
    • Back of upper arms (small children and infants)
  • Your nurse will tell you where the best site is for your child.
  • It is important to rotate injection sites each time.
  • Do not inject enoxaparin where skin is burnt or broken.
Infection sites

Your nurse will show you the steps to give an enoxaparin shot.

When you are ready to give the shot, please follow these steps:


Getting ready

  • Wash your hands thoroughly.
  • Clean your work surface with an alcohol prep pad.
  • Gather the following supplies:
    • Enoxaparin vial or prefilled enoxaparin syringe
    • Alcohol pads
    • #1- 30 unit or 50 unit insulin syringe, if filling syringe from vial
    • Sharps container
    • Chloroprep Sepp® (if you have been instructed to use it)
    • Sterile gauze pad

Withdrawing enoxaparin from a vial

  • Clean the rubber stopper on the vial for 7 seconds with an alcohol pad.
  • Allow the stopper to air dry. Do not blow on the stopper. (Use this time to prepare injection site).
  • Take cap off the end of the syringe. Do not touch the needle.
  • Place the vial on a flat surface and insert needle of the syringe in the rubber stopper.
  • Turn vial and needle upside down to withdraw the correct dose. You may gently tap the end of the syringe on the table to remove air bubbles.
  • When the correct dose is in the syringe, remove needle from the vial.
  • If you are not ready to give the shot, carefully recap needle.

Giving an enoxaparin shot

  • Prepare injection site by wiping with an alcohol pad or Chloroprep Sepp® for 30 seconds.
  • Let area dry for 30 seconds. Do not blow, blot, or wipe area.
  • Remove cap from needle of syringe. If you are using a prefilled enoxaparin syringe do not remove the air bubble in the syringe.
Giving an enoxaparin shot
  • Pinch the cleaned skin and fat between the thumb and first finger. Do not touch the injection site.
  • Hold syringe like a dart between the first finger and thumb.
  • Insert needle quickly straight into the pinched skin or at an angle.
  • Gently push the plunger until you see all the medicine is injected.
  • Take the syringe and needle out. Cover the site with gauze.
  • If using a prefilled syringe, push plunger again to activate safety feature. Then place needle and syringe into sharps container.
  • Do not recap needle.
  • Dispose of other supplies in regular trash, and wash your hands.

Hints for germ free injections

  • Wash your hands with soap and water or use an alcohol-based hand sanitizer. See “Do you know… Clean hands.”
  • Do not use any medicine that has changed its color or has flakes or specks in it.
  • If a sterile syringe part is touched, do not use it. Change the un-sterile part for a sterile part, or start over again.

If you have questions or concerns, please call 901-595-3300 and ask for your child’s primary clinic. If you are calling after hours or on the weekend, ask for the nursing coordinator. If you are outside the Memphis area, dial toll-free 1-866-2STJUDE (1-866-278-5833), and press 0 once the call is connected.


This document is not intended to take the place of the care and attention of your personal physician or other professional medical services. Our aim is to promote active participation in your care and treatment by providing information and education. Questions about individual health concerns or specific treatment options should be discussed with your physician.

St. Jude complies with health care-related federal civil rights laws and does not discriminate on the basis of race, color, national origin, age, disability, or sex.

ATTENTION: If you speak another language, assistance services, free of charge, are available to you. Call 1-866-278-5833 (TTY: 1-901-595-1040).

ATENCIÓN: si habla español, tiene a su disposición servicios gratuitos de asistencia lingüística. Llame al 1-866-278-5833 (TTY: 1-901-595-1040).

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