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Quick facts
- How it is given
- intravenous, subcutaneous
- Type
- human prescription drug
- RxNorm ID
- 1361615
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
INDICATIONS AND USAGE Heparin Sodium Injection is indicated for: Anticoagulant therapy in prophylaxis and treatment of venous thrombosis and its extension; Low-dose regimen for prevention of postoperative deep venous thrombosis and pulmonary embolism in patients undergoing major abdominothoracic surgery or who, for other reasons, are at risk of developing thromboembolic disease (see DOSAGE AND ADMINISTRATION ); Prophylaxis and treatment of pulmonary embolism; Atrial fibrillation with embolization; Treatment of acute and chronic consumptive coagulopathies (disseminated intravascular coagulation); Prevention of clotting in arterial and cardiac surgery; Prophylaxis and treatment of peripheral arterial embolism. Heparin may also be employed as an anticoagulant in blood transfusions, extracorporeal circulation, and dialysis procedures.
About this medicine
DESCRIPTION Heparin is a heterogeneous group of straight-chain anionic mucopolysaccharides, called glycosaminoglycans, having anticoagulant properties. Although others may be present, the main sugars occurring in heparin are: (1) α-L-iduronic acid 2-sulfate, (2) 2-deoxy-2-sulfamino-α-D-glucose 6-sulfate, (3) ß-D-glucuronic acid, (4) 2-acetamido-2-deoxy-α-D-glucose and (5) α-L-iduronic acid. These sugars are present in decreasing amounts, usually in the order (2)> (1)> (4)> (3)> (5), and are joined by glycosidic linkages, forming polymers of varying sizes. Heparin is strongly acidic because of its content of covalently linked sulfate and carboxylic acid groups. In heparin sodium, the acidic protons of the sulfate units are partially replaced by sodium ions. Heparin Sodium Injection, USP is a sterile solution of heparin sodium derived from porcine intestinal mucosa, standardized for anticoagulant activity, in water for injection. It is to be administered by intravenous or deep subcutaneous routes. The potency is determined by a biological assay using a USP reference standard based on units of heparin activity per milligram. Structure of Heparin Sodium (representative subunits): Heparin Sodium Injection, USP (porcine), preserved with parabens, is available as follows : Each mL of the 5,000 units per mL preparation contains: 5,000 USP Heparin units (porcine); 5 mg sodium chloride; 1.5 mg methylparaben; 0.15 mg propylparaben; Water for Injection q.s. Hydrochloric acid and/or sodium hydroxide may have been added for pH adjustment (5.0 to 7.5). Structure of Heparin Sodium
Who should not take it
CONTRAINDICATIONS Heparin sodium should NOT be used in patients with the following conditions: Severe thrombocytopenia; When suitable blood coagulation tests, e.g., the whole blood clotting time, partial thromboplastin time, etc., cannot be performed at appropriate intervals (this contraindication refers to full-dose heparin; there is usually no need to monitor coagulation parameters in patients receiving low-dose heparin); An uncontrollable active bleeding state (see WARNINGS ), except when this is due to disseminated intravascular coagulation.
Warnings
WARNINGS Heparin is not intended for intramuscular use. Fatal Medication Errors Do not use Heparin Sodium Injection as a “catheter lock flush” product. Heparin Sodium Injection is supplied in vials containing various strengths of heparin, including vials that contain a highly concentrated solution of 10,000 units in 1 mL. Fatal hemorrhages have occurred in pediatric patients due to medication errors in which 1 mL Heparin Sodium Injection vials were confused with 1 mL “catheter lock flush” vials. Carefully examine all Heparin Sodium Injection vials to confirm the correct vial choice prior to administration of the drug. Hypersensitivity Patients with documented hypersensitivity to heparin should be given the drug only in clearly life-threatening situations (see ADVERSE REACTIONS, Hypersensitivity ). Hemorrhage Hemorrhage can occur at virtually any site in patients receiving heparin. An unexplained fall in hematocrit, fall in blood pressure or any other unexplained symptom should lead to serious consideration of a hemorrhagic event. Heparin sodium should be used with extreme caution in disease states in which there is increased danger of hemorrhage. Some of the conditions in which increased danger of hemorrhage exists are: Cardiovascular —Subacute bacterial endocarditis, severe hypertension. Surgical —During and immediately following (a) spinal tap or spinal anesthesia or (b) major surgery, especially involving the brain, spinal cord, or eye. Hematologic —Conditions associated with increased bleeding tendencies, such as hemophilia, thrombocytopenia and some vascular purpuras. Gastrointestinal —Ulcerative lesions and continuous tube drainage of the stomach or small intestine. Other —Menstruation, liver disease with impaired hemostasis. Coagulation Testing When heparin sodium is administered in therapeutic amounts, its dosage should be regulated by frequent blood coagulation tests. If the coagulation test is unduly prolonged or if hemorrhage occurs, heparin sodium should be promptly discontinued (see OVERDOSAGE ). Thrombocytopenia Thrombocytopenia has been reported to occur in patients receiving heparin with a reported incidence of up to 30%. […]
Reported side effects
ADVERSE REACTIONS To report SUSPECTED ADVERSE REACTIONS, contact Fresenius Kabi USA, LLC at 1-800-551-7176 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. Hemorrhage Hemorrhage is the chief complication that may result from heparin therapy (see WARNINGS ). An overly prolonged clotting time or minor bleeding during therapy can usually be controlled by withdrawing the drug (see OVERDOSAGE ). It should be appreciated that 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: (a) Adrenal hemorrhage, with resultant acute adrenal insufficiency, has occurred during anticoagulant therapy. Therefore, such treatment should be discontinued in patients who develop signs and symptoms of acute adrenal hemorrhage and insufficiency. Initiation of corrective therapy should not depend on laboratory confirmation of the diagnosis, since any delay in an acute situation may result in the patient’s death. (b) Ovarian (corpus luteum) hemorrhage developed in a number of women of reproductive age receiving short- or long-term anticoagulant therapy. This complication, if unrecognized, may be fatal. (c) Retroperitoneal hemorrhage. Thrombocytopenia, Heparin-induced Thrombocytopenia (HIT) and Heparin-induced Thrombocytopenia and Thrombosis (HITT) and Delayed Onset of HIT and HITT See WARNINGS . Local Irritation Local irritation, erythema, mild pain, hematoma or ulceration may follow deep subcutaneous (intrafat) injection of heparin sodium. These complications are much more common after intramuscular use, and such use is not recommended. Hypersensitivity Generalized hypersensitivity reactions have been reported, with chills, fever and urticaria as the most usual manifestations, and asthma, rhinitis, lacrimation, headache, nausea and vomiting, and anaphylactoid reactions, including shock, occurring more rarely. Itching and burning, especially on the plantar side of the feet, may occur (see WARNINGS and PRECAUTIONS ). […]
Interactions with other medicines
Drug Interactions Oral Anticoagulants —Heparin sodium may prolong the one-stage prothrombin time. Therefore, when heparin sodium is given with dicumarol or warfarin sodium, a period of at least five hours after the last intravenous dose or 24 hours after the last subcutaneous dose should elapse before blood is drawn, if a valid prothrombin time is to be obtained. Platelet Inhibitors —Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet- aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. Other Interactions —Digitalis, tetracyclines, nicotine or antihistamines may partially counteract the anticoagulant action of heparin sodium. Intravenous nitroglycerin administered to heparinized patients may result in a decrease of the partial thromboplastin time with subsequent rebound effect upon discontinuation of nitroglycerin. Careful monitoring of partial thromboplastin time and adjustment of heparin dosage are recommended during coadministration of heparin and intravenous nitroglycerin.
If too much is taken
OVERDOSAGE Symptoms Bleeding is the chief sign of heparin overdosage. Nosebleeds, blood in urine or tarry stools may be noted as the first sign of bleeding. Easy bruising or petechial formations may precede frank bleeding. Treatment Neutralization of Heparin Effect —When clinical circumstances (bleeding) require reversal of heparinization, protamine sulfate (1% solution) by slow infusion will neutralize heparin sodium. No more than 50 mg should be administered, very slowly , in any 10 minute period. Each mg of protamine sulfate neutralizes approximately 100 USP heparin units. The amount of protamine required decreases over time as heparin is metabolized. Although the metabolism of heparin is complex, it may, for the purpose of choosing a protamine dose, be assumed to have a half-life of about 1/2 hour after intravenous injection. Administration of protamine sulfate can cause severe hypotensive and anaphylactoid reactions. Because fatal reactions often resembling anaphylaxis have been reported, the drug should be given only when resuscitation techniques and treatment of anaphylactoid shock are readily available. For additional information consult the labeling of Protamine Sulfate Injection, USP products.
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 1 September 2021. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.