HYPERSENSITIVITY REACTIONS FROM ANTICOAGULIANTS

Abstract

Anticoagulants, including heparins, coumarins, direct thrombin inhibitors (hirudins) are the most widely used drugs. Based on various mechanisms all of them can provoke immediate or delayed hypersensitivity reactions that have different clinical manifestations and severity. Anticoagulants most often induce several skin reactions including delayed type hypersensitivity reactions and rarely immediate hypersensitivity or skin necrosis. Heparin induced thrombocytopenia is life-threatening complication of treatment with heparins that occurs in 5–14 days. Diagnosis is based on clinical findings – thrombocytopenia, thrombotic events and no alternative causes of thrombocytopenia. Cross reactivity between unfractionated and the different low molecular weight heparins and heparinoids has been observed, switch to the other class of anticoagulants is recommended in case of allergy to heparins.