Heparin Sodium Injection - an anticoagulant

Heparin is in the news after what appear to be serious allergic reactions by a small number of patients to this anticoagulant when used in high dosages. The FDA and Baxter, the maker of about half of all the Heparin used, are still unclear on why some 350 patients have experienced problems, some very serious, usually immediately following injection of their Heparin in high dosages.

The FDA's release on Heparin is here and the information appears to be restricted to the following high dosage Heparin products from Baxter Pharmaceuticals:

Products affected are: Baxter’s Heparin Sodium Injection multiple-dose vials (1000 units/mL concentration, 10 mL and 30 mL vials; 5000 units/mL concentration, 10 mL vials; and 10,000 units/mL, 4 mL vials).

Note that the concern is with high doses of Heparin and not the normal small amounts commonly used for intravenous flush or other medical uses. Heparin remains an important