The following clinically significant adverse reactions are described elsewhere in the labeling:
The following adverse reactions have been identified during post approval use of heparin sodium. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Hemorrhage is the chief complication that may result from heparin therapy [see Warnings and Precautions (5.2)]. An overly prolonged clotting time or minor bleeding during therapy can usually be controlled by withdrawing the drug [see Overdose (10)]. 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:
Thrombocytopenia, Heparin-induced Thrombocytopenia (HIT) (With or Without Thrombosis) and Delayed Onset of HIT (With or Without Thrombosis): [see Warnings and Precautions (5.3, 5.4)]
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.
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 site of the feet, may occur [see Warnings and Precautions (5.7)].
Episodes of painful, ischemic, and cyanosed limbs been reported with heparin use.
Elevations of serum aminotransferases
Significant elevations of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels have occurred in a high percentage of patients (and healthy subjects) who have received heparin.
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 also been reported.
Reactions which may occur because of the solution or the technique of administration include febrile response, infection at the site of injection, venous thrombosis or phlebitis extending from the site of injection, extravasation, and hypervolemia.
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