For example, it is needed to carboxylate specific glutamic acid residues on prothrombin.
However, in the case of the second generation superwarfarins intended to kill warfarin-resistant rodents, the time of vitamin K administration may need to be prolonged to months, in order to combat the long residence time of the poison.
They have been largely superseded by second-generation anticoagulants because warfarin-resistant rodents have become more common.
[6] Anisindione, fluindione, and phenindione are oral anticoagulant medicines with actions similar to warfarin.
However, the indandiones are generally more toxic than warfarin, with hypersensitivity reactions involving many organs and sometimes resulting in death.