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Enoxaparin: Injecting at Home

What is enoxaparin?

Enoxaparin​ is a blood thinner (anticoagulant). It works by changing the normal way the blood clots together. It helps prevent unwanted blood clots or existing blood clots from getting bigger.

Enoxaparin comes as a clear liquid for injection.

What to expect before going home

  1. You will be given information that explains why your child is taking enoxaparin.
  2. The nurse or pharmacist will teach you how to give your child the enoxaparin needles. We will help you learn to give your child’s enoxaparin needles by yourself before you go home.
  3. You will be given prescriptions for enoxaparin.
  4. You will be given prescriptions for the right size of syringes. They are called insulin syringes and come in sizes of 30 units, 50 units, and 100 units. The prescriptions for the syringes and medicine should be on separate pages, as some families may not need to get syringes.
  5. We will tell the medical team of your child’s discharge date as soon as it is known so that they can come to see you. If it is not possible for them to see you (if your child is discharged on a weekend) they will call you in the following week.
  6. The medical team will make sure that you know about blood work appointments.

How long will your child need to take enoxaparin?

Your child’s thrombosis team will decide how long your child needs to take enoxaparin, depending on the reason for your child’s treatment.

To decide when to stop your child’s treatment, the doctor may do follow-up imaging tests, such as an MRI, echocardiogram, ultrasound, or a CT scan.

The medical team will arrange follow-up clinic appointments and call you with the dates and the time.

Keeping track of blood work results

You will discuss where and when the blood work will be done with the medical team and thrombosis team.

When should you call your child’s medical or thrombosis team?

 Call the medical or thrombosis team if your child:

  • hits their head or has a fall
  • has bruises that are large or cannot be explained
  • has a nose bleed that is hard to stop
  • has bowel movements that are black or red
  • has new bleeding from gums when brushing the teeth
  • will be having any medical or dental procedures or surgeries

While your child is taking enoxaparin

Your child may bleed and bruise more easily.

  • Please check with the medical team about what activities your child is allowed. Contact sports are not recommended.
  • Your child may need to wear a Medic Alert bracelet if on this medication for a long time. You can discuss this with the medical team.

Storing enoxaparin

Enoxaparin does not require refrigeration and can be kept at room temperature (less than 25°C). Once you open the bottle, it can be used for 28 days only. After 28 days the bottle must be thrown away, even if there is still medicine in it.

How much to give

This can be no less than 10 hours and no more than 14 hours between doses.

It is available in several different strengths. The dosing information below applies to the 100 mg/mL (3 mL) multidose vials.

Enoxaparin is usually injected using insulin syringes that are specially designed for injections into the skin. It is important to note that the volume is measured in “units” on an insulin syringe, and that 1 unit on the insulin syringe is equal to 1 mg of enoxaparin.

Your child has been prescribed _______ mg of enoxaparin each dose. This dose is equivalent to _______units on an insulin syringe.

Drawing up enoxaparin

Before giving your child enoxaparin, you first need to draw up the medicine from the bottle. Make sure to check the date on the medication bottle to make sure it has not expired.
You will need:

  • Enoxaparin bottle
  • Insulin 30, 50, or 100 unit syringe (use only insulin syringes). You must use a new needle and syringe each time.
  • Alcohol swab
  • Cotton ball

To draw up enoxaparin:

  1. Wash your hands.
  2. Clean the rubber stopper on the medicine bottle with an alcohol swab. Wait 30 seconds for the alcohol to dry.
  3. Remove the cap from the needle and syringe. Put the needle through the rubber stopper on the medicine bottle.
  4. Turn the bottle upside down with the syringe in it. Ensure the tip of the needle is in the solution.
  5. Slowly pull down on the plunger of the syringe until you have a bit more than the required number of units. If you have trouble pulling out the medicine, inject a bit of air into the bottle, and try again.
  6. Check the syringe for any air bubbles. Tap the syringe to make any air bubbles float to the top.
  7. Slowly push up on the plunger to the desired amount. If you have pushed out too much, pull back again on the syringe to the correct volume. Recheck for air bubbles.
  8. Lift off the medicine bottle from the syringe. Be sure not to touch the exposed needle to any surfaces. It is now ready to be given to your child.

Where to inject enoxparin

Enoxaparin is injected into the fatty layer just below the skin. This is called the subcutaneous (SC) layer. Safe areas of injection are: thighs and upper arms. Do not use the buttocks. 

SC Injection With Insulin Syringe
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  • Thighs: Top front side and outer parts of thigh only. Do not use the inner thigh or back of the thigh. Divide the thigh into thirds; the injection site is in the middle third section.
Thigh Injection Site
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  • Upper Arms:  Fatty area on the side and back of the arm. This site is only for infants older than 4 to 6 months. Divide the upper arm into thirds; the injection site is in the middle third section.
Upper Arms Injection Site
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When giving your child the injection:

  1. Choose the injection spot. Clean the skin with soap and water (you do not need to use alcohol swab). Try to change injection sites with each injection you give. For example, inject into the left thigh in the morning and right thigh at night.
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  1. Gently squeeze up a well-defined fold of skin and fat with the thumb and index finger.
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  1. Hold the shaft of the syringe in a dart fashion, insert needle directly through the skin at a right angle (90-degree angle) quickly just into the fatty layer.
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  1. Move hand into position to direct plunger.  Do not move needle tip once it is inserted.
  2. Give drug slowly to reduce stinging, firmly push plunger down as far as it will go.
  3. Pull the needle out gently at the same angle you put it in. As you take out the needle, let go of the skin roll.
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  1. Apply firm pressure with a cotton ball to the injection site for 3 to 5 minutes following each injection to reduce the chance of bruising.
  2. Do not rub the area as it may irritate the skin.
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  1. Put the needle and syringe in a thick, plastic bottle or sharps container with a lid. This is for safety. When the container is full, bring it to your local pharmacy. They can safely dispose of it for you. Do not put it in your regular garbage.

Personal stories about the use of low molecular weight heparins

Two families share their experiences with using low molecular weight heparins. This video will help to answer any questions you may have if you or someone you know will be taking this medication.

Key Points

  • Enoxaparin is an anticoagulant (blood thinner).
  • Enoxaparin helps prevent unwanted blood clots or existing clots from getting bigger
  • It is given for as long as your child needs it.
  • Enoxaparin can be injected into the thigh or upper arm (for infants older than 4 to 6 months).
  • You will be given prescriptions for the right size of syringes. They are called insulin syringes and come in sizes of 30 units, 50 units, and 100 units.
  • Enoxaparin does not require refrigeration, and can be kept at room temperature.
  • Once opened the bottle can be used for 28 days only.
  • 1 unit on the insulin syringe = 1 mg of enoxaparin.

Darlene Castle, RN
Elaine Lau BScPhm, PharmD, MSc, RPh
Carol Chan, BScPhm, ACPR, RPh 


At SickKids:

The Thrombosis Team

The Thrombosis Team at The Hospital for Sick Children operates 24 hours a day, 7 days of the week to respond to urgent calls from families of children and teens. If you need immediate attention, please call (416) 813-7500 and ask the switchboard operator to page the Thrombosis team member on call.

The Thrombosis Nurse Coordinator will arrange Thrombosis clinic appointments and call you with the dates and times.  Families may call (416) 814-5859 (Thrombosis Clinic) if they have not heard from the coordinator within 2-3 weeks after leaving the hospital with an appointment time.

Keeping Track of Blood Work Results

  • Blood tests can be done at SickKids. You will discuss where and when the blood work will be done with the Thrombosis Nurse.  Please call Thrombosis Nurse in 1 week after discharge to arrange next blood work.
  • Notify the Thrombosis Team on the day your child has had blood work done by calling the Thrombosis Nurse at (416) 813-5859 on Monday to Friday. The Thrombosis team will call you when they have received the results and will let you know if anything needs to be changed.  You should receive a call from the Thrombosis Team whether or not changes are required.