The information in this profile may be out-of-date. It was last revised in 1996. EXTOXNET no longer updates this information, but it may be useful as a reference or resource.

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Pesticide Information Profiles

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Revised 9/95.


TRADE OR OTHER NAMES: The active ingredient warfarin is found in a variety of commercial rodenticides. Some trade names for products containing warfarin include Cov-R-Tox, Co-Rax, d-Con, Dethmor, Mar-Fin, Rattunal, Rax, Rodex, Rodex Blox, Rosex, Solfarin, Tox-Hid, Warf, and Warfarat (207, 369, 375). Warfarin is called coumafene in France, zoocoumarin in the Netherlands and Russia, and coumarin in Japan (1, 207, 372).

REGULATORY STATUS: Warfarin is a general use pesticide (GUP). Check with specific state regulations for local restrictions which may apply. The Signal Word for technical and high concentrations of warfarin is "Danger". The Signal Word "Caution" is used for low concentrations and ready-to-use baits (207).

INTRODUCTION: Warfarin was the first anticoagulant rodenticide introduced and was first registered for use in the United States in 1952 (369, 377). Warfarin is used for controlling rats and house mice in and around homes, animal and agricultural premises, and commercial and industrial sites. It is odorless and tasteless and effective in very low dosages. Action is not rapid; usually about a week is required before a marked reduction in the rodent population is noticeable. Rodents do not tend to become bait-shy after once tasting warfarin; they continue to consume it until its anti-clotting properties have produced death through internal hemorrhaging. The prothrombin content of the blood is reduced and internal bleeding is induced. Repeated ingestion is needed to produce toxic symptoms. This rodenticide can be used year-after-year wherever a rodent problem exists. Mice are harder to control than rats, and complete control may take a longer period. Recently, resistant strains of rats and mice are developing (207, 369, 375, 377).Warfarin is only slightly dangerous to humans and domestic animals when used as directed, but care must be taken with young pigs, which are especially susceptible (1).

FORMULATION: Warfarin comes in water soluble, ready-to-use bait, concentrate, powder, liquid concentrate, nylon pouch, coated talc and dust formulations. The compound also comes in mixed formulations with pindone, calciferol, and sulphaquinoxaline. It is considered compatible with other rodenticides (1, 242, 207).





Physical Properties:

Exposure Guidelines:


P. O. Box 7190
537 Atlas Avenue (53714)
Madison, WI 53707

Prentiss, Inc.
CB 2000
Floral Park, NY 11001


References for the information in this PIP can be found in Reference List Number 10

DISCLAIMER: The information in this profile does not in any way replace or supersede the information on the pesticide product label/ing or other regulatory requirements. Please refer to the pesticide product label/ing.