Heparin is a naturally occurring anticoagulant produced by basophils and mast cells. Heparin acts as an anticoagulant, preventing the formation of clots and extension of existing clots within the blood. While heparin does not break down clots that have already formed (unlike tissue plasminogen activator), it allows the body's natural clot lysis mechanisms to work normally to break down clots that have formed. Heparin Sodium is the sodium salt of the sulfated glycosaminoglycans of mixed mucopolysaccharides varying in molecular weights. Purity ≥99%