Dexrazoxane reduces antithrombin activity: Five case reports

Abstract Dexrazoxane prevents anthracycline-induced cardiotoxicity and treats anthracycline extravasation. Thrombosis is not a major adverse effect of dexrazoxane use but their relationship has been reported. Here, we describe five patients in whom antithrombin activity decreased after dexrazoxane injections. All five patients were prescribed dexrazoxane to protect the soft tissues from anthracycline extravasation during chemotherapy for hematological malignancies. This led to a reduction in antithrombin activity after a median of 4 days from the first dexrazoxane injection. The activity levels recovered several days later, and one of the patients developed deep vein thrombosis. There was no explanation other than dexrazoxane use, prompting us to speculate that dexrazoxane reduces antithrombin activity. We infer that a decrease in antithrombin activity triggers thrombosis after dexrazoxane injection. Based on these cases and a review of previous reports on dexrazoxane and thrombosis, it is recommended that clinicians monitor antithrombin decline and thrombosis development in patients undergoing dexrazoxane treatment.