Side effects

These include:

• haemorrhage, reversed by protamine sulphate
• thrombocytopaenia - this is due to a direct effect of heparin on platelets, which generally improves with cessation of heparin. There also appears to be an immune mechanism that occurs 6-12 days after commencing heparin therapy. This latter cause of thrombocytopaenia via heparin-associated immune mediated aggregation of platelets may predispose to formation of platelet thrombus and disseminated intravascular coagulation, in addition to thrombocytopaenia.
• other side effects include alopecia and osteoporosis