Monograph: |
Parnaparin sodium
Parnaparin sodium is prepared by hydrogen peroxide and copper(II) acetate depolymerisation of heparin obtained from the intestinal mucosa of pigs and cattle. The majority of the components have a 2-O-sulpho-alpha-L-idopyranosuronic acid structure at the non-reducing end and a 2-Ar,6-O-disulpho-D-glucosamine structure at the reducing end of their chain. The mass-average molecular mass ranges between 4000 and 6000, with a characteristic value of about 5000. The mass percentage of chains lower than 3000 is not more than 30%. The degree of sulphation is 2.0 to 2.6 per disaccharide unit. The Ph. Eur. specifies that potency is not less than 75 units and not more than 110 units of anti-factor Xa activity per mg with reference to the dried substance and that the ratio of anti-factor Xa activity to anti-factor IIa (antithrombin) activity is between 1.5 and 3.0.
Parnaparin sodium is a low-molecuiar-weight heparin with anticoagulant activity used in the prevention of postoperative venous thrombo-embolism. For general surgical procedures it is given by subcutaneous injection in a dose of 3200 units 2 hours before the procedure, followed by 3200 units once daily for 7 days or until the patient is fully ambulant. For higher risk or orthopaedic patients a dose of 4250 units is given 12 hours before the procedure, followed by 4250 units 12 hours postoperatively and then once daily for 10 days.
|