Heparin Sodium Injection Side Effects Center

Last updated on RxList: 2/26/2019
Heparin Sodium Injection Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

Last reviewed on RxList 2/26/2019

Heparin (heparin sodium injectable) is a heterogeneous group of straight-chain anionic mucopolysaccharides, called glycosaminoglycans that have anticoagulant properties. They are derived from porcine intestinal mucosa and standardized into international units. Heparin is used to help prevent clot formation (for example, venous thrombosis, pulmonary embolisms, coagulopathies and coronary artery clots). Heparin is available as generic heparin and under other generic brand names. Common side effects of Heparin include:

  • easy bleeding and bruising;
  • pain,
  • redness,
  • warmth, or
  • skin changes where the medicine was injected;
  • itching of your feet; or
  • bluish-colored skin.

Heparin is available in vials at strengths of 1000, 5000, 10,000 and 20,000 units per ml. Dosage depends on the coagulation problem; many initial doses start with 5000 units IV, but this can change depending on the problem; guidelines for dosages are available. If benzyl alcohol is listed as a preservative for the Heparin preparation, do not use in neonates and infants or nursing mothers. If preparations without benzyl alcohol are used in pediatric patients, the initial dose is usually 50 units per Kg but a pediatric specialist should be consulted. Thrombocytopenia, Heparin-induced thrombocytopenia (HIT) and Heparin-induced thrombocytopenia and thrombosis (HITT) are serious side effects of heparin. Drugs like digitalis, tetracycline, nicotine or antihistamines may reduce the effect of Heparin. Heparin use with antiplatelet medications may induce bleeding. Patients on Heparin should be aware of the increased possibility of bleeding due to trauma, especially head trauma.

Our Heparin Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Heparin Sodium Injection Consumer Information

Get emergency medical help if you have signs of an allergic reaction: nausea, vomiting, sweating, hives, itching, trouble breathing, swelling of your face, lips, tongue, or throat, or feeling like you might pass out.

Heparin may cause you to bleed more easily, which can be severe or life-threatening. You may also have bleeding on the inside of your body. Seek emergency medical attention if you have:

  • skin warmth or discoloration;
  • chest pain, irregular heartbeats;
  • shortness of breath, dizziness, anxiety, sweating;
  • any unusual bleeding or bruising;
  • severe pain or swelling in your stomach, lower back, or groin;
  • dark or blue-colored skin on your hands or feet;
  • nausea, vomiting, loss of appetite;
  • unusual tiredness;
  • any bleeding that will not stop; or
  • nosebleed, blood in your urine or stools, black or tarry stools, or coughing up blood or vomit that looks like coffee grounds.

Heparin can cause you to have bleeding episodes while you are using it and for several weeks after you stop.

Bleeding may be more likely in older adults, especially women over 60 years of age

Stop using heparin and call your doctor at once if you have:

  • skin changes where the medicine was injected;
  • fever, chills, runny nose, or watery eyes;
  • easy bruising, unusual bleeding, purple or red spots under your skin; or
  • signs of a blood clot--sudden numbness or weakness, problems with vision or speech, swelling or redness in an arm or leg.

Common side effects may include:

  • unusual bleeding or bruising;
  • uncontrolled bleeding;
  • allergic reactions; or
  • abnormal liver function tests.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Heparin Sodium Injection (Heparin Sodium Injection)


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Heparin Sodium Injection Professional Information


Postmarketing Experience

The following adverse reactions have been identified during post approval use of HEPARIN SODIUM INJECTION. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency.

  • Hemorrhage – Hemorrhage is the chief complication that may result from heparin therapy [see WARNINGS AND PRECAUTIONS]. Gastrointestinal or urinary tract bleeding during anticoagulant therapy may indicate the presence of an underlying occult lesion. Bleeding can occur at any site but certain specific hemorrhagic complications may be difficult to detect including:
    • Adrenal hemorrhage, with resultant acute adrenal insufficiency, has occurred with heparin therapy, including fatal cases.
    • Ovarian (corpus luteum) hemorrhage developed in a number of women of reproductive age receiving short- or long-term heparin therapy.
  • Retroperitoneal hemorrhage.
  • HIT and HITT, including delayed onset cases [see WARNINGS AND PRECAUTIONS].
  • Local irritation – Local irritation, erythema, mild pain, hematoma, or ulceration have occurred following deep subcutaneous (intrafat) injection of heparin sodium. Because such reactions occur more frequently after intramuscular administration, the IM route is not recommended.
  • Histamine-like reactions – Such reactions have been observed at the site of injection. Necrosis of the skin has been reported at the site of subcutaneous injection of heparin, occasionally requiring skin grafting [see WARNINGS AND PRECAUTIONS].
  • Hypersensitivity – Generalized hypersensitivity reactions have been reported with chills, fever, and urticaria as the most usual manifestations; asthma, rhinitis, lacrimation, headache, nausea and vomiting, and anaphylactoid reactions, including shock, occur less frequently. Itching and burning, especially on the plantar site of the feet, may occur.
  • Elevations of serum aminotransferases – Significant elevations of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels have occurred in patients who have received heparin.
  • Others – Osteoporosis following long-term administration of high doses of heparin, cutaneous necrosis after systemic administration, suppression of aldosterone synthesis, delayed transient alopecia, priapism, and rebound hyperlipemia on discontinuation of heparin sodium have been reported.

Read the entire FDA prescribing information for Heparin Sodium Injection (Heparin Sodium Injection)


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© Heparin Sodium Injection Patient Information is supplied by Cerner Multum, Inc. and Heparin Sodium Injection Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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