Crimidine is a convulsant poison used as a rodenticide. Crimidine was originally known by its product name, Castrix. It was originally produced in the 1940s by the conglomerate, IG Farben.[1] It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities.[2] It is also no longer used in the United States as a rodenticide, but is still used to this day in other countries.