Enoxaparin is a type of low molecular weight heparin and belongs to the group of medications known as anticoagulants or antithrombotic agents. These medications reduce the clotting ability of the blood and can reduce the risk of harmful blood clots forming in blood vessels.

Enoxaparin is used to prevent and treat deep vein thrombosis (DVT), which is a condition that leads to the formation of blood clots in the blood vessels in the leg. These blood clots sometimes travel to the lungs and block blood vessels there, resulting in a serious condition known as pulmonary embolism.

Enoxaparin may be used to prevent DVT in people who are bedridden due to serious illness (heart failure, severe chest infections, or respiratory failure), or after they have had certain types of surgery (such as hip or knee replacements; or abdominal, gynecological, urological, or colorectal surgery). It may be used to prevent clotting in the blood outside the body during hemodialysis. Enoxaparin is also used to treat DVT with or without pulmonary embolism.

Enoxaparin is also used in combination with ASA to treat people who have unstable angina and non-Q-wave heart attacks (a type of heart attack that does not involve the full thickness of the heart wall).

This medication is also used to treat a particular type of heart attack called ST-segment elevation myocardial infarction (STEMI) and for Percutaneous Coronary Intervention (PCI) to open up the coronary arteries after a heart attack.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are being given this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

Enoxaparin is injected under the skin (subcutaneously, not intramuscularly).

The recommended dose varies according to the individual and the condition being treated. 

For acute-ST-segment elevation heart attacks, you will receive a single dose of 30 mg of enoxaparin injected into a vein. Subsequent doses are injected subcutaneously every 12 hours, and are calculated as 1 mg per kilogram of body weight. This is usually continued for 8 days or until release from the hospital.

For the treatment of unstable angina or Non-Q-Wave heart attacks, the dose is calculated as 1 mg per kilogram of body weight, injected subcutaneously every 12 hours. To treat deep vein thrombosis (DVT), the recommended dose is 1.5 mg per kilogram of body weight, injected subcutaneously once daily or 1 mg per kilogram of body weight, injected subcutaneously every 12 hours.

If enoxaparin is being used to prevent blood clots when you are having knee or hip replacement surgery, the recommended dose is 30 mg injected subcutaneously every 12 hours, starting 12 to 24 hours after surgery. This is usually used for 7 to 14 days.

To prevent blood clots caused by abdominal, colorectal, gynecological, or urological surgery, the recommended dose is 40 mg injected subcutaneously 2 hours before surgery and continuing once daily for 7 to 10 days. If there is no risk of bleeding, but high risk of developing blood clots, this dose may be continued for up to 4 weeks.

To prevent blood clots caused by other medical conditions, such as when you have an illness and have limited ability to move about, the recommended dose is 40 mg injected subcutaneously, once daily. The use of enoxaparin in these situations is usually short-term (6 to 11 days).

Steps to use the medication:

1. Before injecting enoxaparin, wash your hands and clean the area of skin where you will inject with an alcohol swab. Do not rub the area to be injected. Only use the injection if the solution appears clear and colourless or pale yellow.
2. Lie down and pinch a fold of skin (usually in the lower abdomen at least 5 cm away from your belly button and out towards the sides) between your finger and thumb. Choose a different place of the lower abdomen for each injection.
3. Remove the needle cover by pulling it straight off the syringe.
4. Push the entire needle vertically into the skin in one smooth quick motion, and then press down on the syringe plunger to inject the medication. Make sure you are holding the skin fold the entire time you are injecting the needle and pressing down on the syringe plunger.
5. After giving the injection, remove the needle from your skin. A protective sleeve will automatically cover the needle. Use an alcohol swab to apply light pressure to the injection area for several seconds. Do not rub the site afterwards.
6. Dispose of the syringe and needle safely (using a sharps container). Each syringe is for single use only.

To prevent clot formation during hemodialysis, the dose varies depending on your circumstances and the medication will be given by injection into the tubing that carries your blood to the dialysis machine.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using this medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. If you miss an injection, take it as soon as possible and continue with your regular schedule. If it is almost time for your next injection, skip the missed dose and continue with your regular dosing schedule. Do not inject a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from heat, and keep it out of the reach of children. If you are using the multiple dose vial, do not store it for more than 28 days after the first use.

Prefilled Syringes

120 mg/0.8 mL
Each syringe contains 120 mg of enoxaparin sodium in 0.8 mL of water for injection. The solution is preservative-free and intended for use as a single-dose injection.

150 mg/1 mL
Each syringe contains 150 mg of enoxaparin sodium in 1 mL of water for injection. The solution is preservative-free and intended for use as a single-dose injection.

The 120 mg/0.8 mL and 150 mg/1 mL syringes are imprinted with a graduation scale of 1 mL with major increments of 0.1 mL and minor increments of 0.02 mL.

The pH of the syringe and multiple dose solution is 5.5 to 7.5 with an approximate anti-factor Xa activity of 100 IU/1 mg of drug (with reference to the WHO First International Low Molecular Weight Heparin Reference Standard). Nitrogen is used in the headspace to inhibit oxidation.

Do not use enoxaparin if you:

• are allergic to enoxaparin or any ingredients of the medication
• are allergic to other low molecular weight heparins or heparin
• are actively bleeding
• are receiving spinal or epidural anesthesia and will be needing multiple doses of enoxaparin
• currently have or have previously had a history of heparin-induced thrombocytopenia (decrease in the number of platelets) or a positive in vitro platelet-aggregation test while using enoxaparin
• have decreased platelets
• have a hemorrhagic cerebrovascular accident (bleeding into tissues of the brain)
• have acute or sub-acute bacterial endocarditis (heart infection)
• have an active gastric (stomach) or duodenal (intestinal) ulcer
• have eye problems due to diabetes or hemorrhage (bleeding)
• have injuries to and operations on the brain, spinal cord, eyes, or ears
• have major blood clotting disorders
• have other conditions or diseases involving an increased risk of bleeding
• have severe uncontrolled high blood pressure

People who need repeated doses of enoxaparin should not receive anesthetics that are injected into the spine or epidural space.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• hardening of skin or lump at injection site
• hair loss
• pain or redness and bruising at site of injection

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• abdominal pain
• bleeding from a surgical wound
• bone pain or fractures (bone thinning when used for more than 3 months)
• chest pain
• confusion
• dizziness
• hair loss
• headache
• inability to move hands or feet or other parts of body (paralysis), or sudden back pain or tenderness
• rapid or unusual heartbeat
• shortness of breath
• signs of bleeding (such as nosebleeds, blood in the urine, bleeding gums, coughing or throwing up of blood, easy bruising, increased menstrual bleeding)
• signs of a blood clot in the arm or leg (tenderness, pain, swelling, warmth, or redness in the arm or leg) or lungs (difficulty breathing, sharp chest pain that is worst when breathing in, coughing, coughing up blood, sweating, or passing out)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• sudden change or loss of vision
• vomiting

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a severe allergic reaction (such as difficulty breathing; skin rash or hives; swelling of the lips, mouth, or throat)
• signs of a stroke (e.g., sudden severe headache; loss of coordination; confusion; difficulty speaking or understanding speech; vision problems in one or both eyes; or weakness or numbness, especially on one side of the body)
• signs of bleeding in the stomach or digestive tract (e.g., bloody, black, or tarry stools; spitting up of blood; vomiting blood or material that looks like coffee grounds)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Bleeding: The most serious risk associated with enoxaparin is bleeding in any tissue or organ. It is extremely important to have regular blood tests (as prescribed by your doctor) to ensure that the correct level of blood thinning is occurring. People with an increased risk of bleeding (such as seniors) should be closely monitored by their doctors while taking this medication. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible.

Body weight: The safety and efficacy of enoxaparin for people of high weight (e.g., over 120 kg) and low weight (e.g., under 45 kg) have not been fully established. If you have a high or low weight, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Kidney problems: Decreased kidney function or kidney disease can cause this medication to build up in the body, causing increased side effects. If you have kidney problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver problems: If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Medical conditions: If you have malignant disease; a history of thrombophilia and known deficiency in antithrombin III, protein C or protein S, or APC resistance; are bedridden due to infections with septic shock; severe COPD complicated by right heart failure, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Osteoporosis: Prolonged use of this medication (i.e., longer than 3 months) has been associated with the development of osteoporosis. If you have osteoporosis or are at risk for developing osteoporosis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Platelets: Platelets are blood cells that cause blood to clot. While you are taking enoxaparin, your doctor will also be monitoring your platelet count. If your platelet level drops very suddenly, you may have to stop this medication and switch to another type of medication. Make sure to tell your doctor if you have had any problems with low platelets or platelet defects in the past.

Prosthetic heart valves: There have been reports of people with prosthetic heart valves who developed clots in their valves when treated with low molecular weight heparin medications, like enoxaparin. Your doctor will need to monitor you closely while you are taking enoxaparin.

Spinal/epidural hematomas (a collection of blood, usually clotted): There have been cases of spinal bleeding and blood clots when enoxaparin is used along with spinal or epidural anesthesia. These spinal blood clots may lead to long-term or permanent paralysis. The risk is greater with higher treatment doses of enoxaparin than with DVT prevention doses and if people are taking other medications that affect blood clotting (e.g., nonsteroidal anti-inflammatory drugs [NSAIDs] such as naproxen or ibuprofen). If you notice a sudden inability to move your body or sudden back pain or tenderness, get medical help immediately.

People who need repeated doses of enoxaparin should not receive anesthetics that are injected into the spine or epidural space.

Stomach or intestinal ulcers: If you have stomach or intestinal ulcers, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

If you do use enoxaparin while you are pregnant, your doctor will need to closely monitor you because of an increased risk of bleeding. Pregnant women should not use enoxaparin from multidose vials that contain benzyl alcohol as a preservative. Benzyl alcohol crosses the placenta and can cause a potentially fatal gasping syndrome in premature or newborn babies. Pregnant women who have artificial heart valves will also need to be closely monitored by their doctors if they use this medication because of a higher risk of developing clots in their heart valves.

Breast-feeding: It is not known if enoxaparin passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

Seniors: Seniors may be at an increased risk of bleeding while using enoxaparin. Your doctor may adjust your dose, especially if you weigh less than 45 kg or have decreased kidney function.

There may be an interaction between enoxaparin and any of the following:

• 5-ASA medications (e.g., mesalamine, olsalazine, sulfasalazine)
• acetylsalicylic acid (ASA)
• aliskiren
• angiotensin converting enzyme inhibitors (ACEIs; captopril, ramipril)
• angiotensin receptor blockers (ARBs; e.g., candesartan, irbesartan, losartan)
• apixaban
• canagliflozin
• clopidogrel
• dabigatran
• dasatinib
• deferasirox
• deoxycholic acid
• dipyridamole
• edoxaban
• eplerenone
• estrogens (e.g., conjugated estrogen, estradiol, ethinyl estradiol)
• heparin
• herbal products that affect blood clotting (e.g., cat's claw, chamomile, fenugreek, evening primrose, feverfew, garlic, ginger, ginseng, turmeric)
• mifepristone
• non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, naproxen)
• obinutuzumab
• omega-3 fatty acids
• other low-molecular-weight heparins (e.g., dalteparin, tinzaparin)
• pentoxifylline
• potassium-sparing diuretics (e.g., amiloride, spironolactone, triamterene)
• potassium supplements (e.g., potassium chloride, potassium citrate)
• progestins (e.g., dienogest, levonorgestrel, medroxyprogesterone, norethindrone)
• rivaroxaban
• selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, fluoxetine, paroxetine, sertraline)
• serotonin-norepinephrine reuptake inhibitors (SNRIs; desvenlafaxine, duloxetine, venlafaxine)
• thrombolytic agents (e.g., alteplase, streptokinase, urokinase)
• ticagrelor
• ticlopidine
• vitamin E
• vorapaxar
• warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.