It is a second-generation 4-hydroxycoumarin derivative and vitamin K antagonist, often called a "super-warfarin" for its added potency and tendency to accumulate in the liver of the poisoned organism.
When first introduced to the UK market in 1980, it was effective against rodent populations that had become resistant to first generation anticoagulants.
It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the Emergency Planning and Community Right-to-Know Act (42 U.S.C.
The lack of vitamin K in the circulatory system reduces blood clotting and will cause death due to internal hemorrhaging.
[clarification needed] Following are acute LD50 values for various animals (mammals):[2] The compound is used as a mixture of four stereoisomers.