Heparin

Heparin is a naturally occurring complex glycosaminoglycan composed of polymers of several carbohydrates including D-glucuronic acid, L-iduronic acid and D-glucosamine, in which the amino groups and some of the hydroxyl groups are sulfated. It has a very high density of negative charge. Heparin is a natural anticoagulant that is produced by the liver, lungs, and other tissues. As a medication, heparin is used as a blood thinner that is injected into muscle or a vein to prevent the formation or breakdown of blood clots. Specifically, it is also used to treat myocardial infarction and unstable angina. As heparin reduces the ability of the blood to form a clot, it may increase the risk of bleeding, which at times can be life-threatening. It should not be used if someone has a fall of hematocrit or blood pressure, severe deficiency of platelets in circulation because it can cause heparin-induced thrombocytopenia. Injection of heparin can cause bruising, back pain, a nosebleed, blood in urine, stools or cough, and may need emergency medical attention.

Certain non-steroidal anti-inflammatory drugs, such as aspirin, diclofenac, ibuprofen, ketoprofen, indomethacin, meloxicam, mefenamic acid etc., can increase the risk of bleeding in subjects using heparin. Patients with untreated hypertension or high blood pressure, liver disease, kidney function impairment, stomach or gastrointestinal disorders should use heparin with extreme caution as these comorbid conditions may predispose the patients to hemorrhage during heparin therapy. Heparin has anti-inflammatory properties and inhibits allergen induced mast cell degranulation and prevents subsequent development of inflammation, bronchial hyperreactivity and asthma. In all mammals including humans, basophils and mast cells produce heparin and store in the secretory granules of these cells to be released only at sites of tissue damage. It is possible that rather than prevent blood coagulation, the primary function of heparin is to give protection against invading bacteria and other exogenous substances such as an allergen. [Laila Noor Islam]