Page 27 - phytochemistry I - PharmD Clinical

Chemical composition:
 It is a large, dextrorotatory, highly acidic polysaccharide molecule
composed of sulfated D-glucosamine and D-glucuronic acid residues.
 The polymer chain contains a repeating disaccharide units of D-
glucosamine N,6- disulfate and D-glucuronic acid 2- sulfate. These
monosaccharide units are linked by α, 1→4 bonds.
 Because of its acidic properties, heparin is also referred to as
heparinic acid.

 Heparin exists as the anion at physiologic pH and is usually administered as the
sodium salt.

 Heparin acts as an anticoagulant by combining with antithrombin III, an α-
glycoprotein, which is synthesized in the liver.

 The heparin-antithrombin III complex inactivates factor Xa and therefore inhibits
the generation of thrombin.

Uses:
 It is believed that heparin to be the anticoagulant of choice, but parenteral

administration precludes its long-term use.
 Heparin is generally given to postoperative patients and to those with acute

infarctions requiring immediate anticoagulant activity.
Rout of administration:
 Heparin is administered intravenously in two ways:
 If hemorrhage occurs, the anticoagulant effects of heparin can be reversed in

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