Description

 
 
Delayed Onset of HIT and HITT 
Heparin-induced thrombocytopenia and heparin-induced thrombocytopenia and thrombosis can occur 
up to several weeks after the discontinuation of heparin therapy. Patients presenting with 
thrombocytopenia or thrombosis after discontinuation of heparin should be evaluated for HIT and 
HITT. 
 
Use in Neonates
This product contains the preservative benzyl alcohol and is not recommended for use in neonates. 
There have been reports of fatal ‘gasping syndrome’ in neonates (children less than one month of age) 
following the administration of intravenous solutions containing the preservative benzyl alcohol. 
Symptoms include a striking onset of gasping respiration, hypotension, bradycardia, and 
cardiovascular collapse. 
 
PRECAUTIONS 
General 
 
Thrombocytopenia, Heparin-induced Thrombocytopenia (HIT) and Heparin-induced 
Thrombocytopenia and Thrombosis (HITT):
see WARNINGS.
Heparin Resistance 
Increased resistance to heparin is frequently encountered in fever, thrombosis, thrombophlebitis, 
infections with thrombosing tendencies, myocardial infarction, cancer and in postsurgical patients. 
Increased Risk to Older Patients, Especially Women 
A higher incidence of bleeding has been reported in patients, particularly women, over 60 years of age. 
Laboratory Tests 
Periodic platelet counts, hematocrits, and tests for occult blood in stool are recommended during the 
entire course of heparin therapy, regardless of the route of administration. (See DOSAGE AND 
ADMINISTRATION.) 
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 5 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 

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NDA 17-037/S-158 
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nitroglycerin. Careful monitoring of partial thromboplastin time and adjustment of heparin dosage are 
recommended during coadministration of heparin and intravenous nitroglycerin.