In Research

The most popular rodenticides used today are anticoagulants, more commonly known as blood thinners.  When these products are used, rodents typically experience mortality between five and eight days after initial feeding on the bait.

First-generation anticoagulants include the active ingredients that were developed as rodenticides before 1970, including warfarin, chlorophacinone and diphacinone.

Second-generation anticoagulants were introduced in the 1970s and 1980s to control rodents that were thought to be resistant to first-generation anticoagulants.  These active ingredients were considered more effective than first-generations at rodent control after just one feeding.  Second-generation compounds registered in the United States include brodifacoum, bromadiolone, difenacoum and difethialone.


Many Kaput® products are manufactured with warfarin.  Scimetrics, the manufacturers of Kaput baits, is dedicated to developing the most effective solutions to rodent control issues, while maintaining the lowest risk possible to non-targets, including pets and wildlife.

First-generation and second-generation anticoagulants eliminate rodents over the same period of time. As you can see from the chart, based on studies by Genesis Laboratories, first-generation active ingredients are effective within the same time period as second-generation actives – with peak control at day six of baiting.

Warfarin is metabolized more quickly than second-generation anticoagulants. According to the United States Environmental Protection Agency, second-generation anticoagulants remain in animal tissues longer than first-generation anticoagulants, meaning that “second-generation products pose greater risks to nontarget species that might feed on bait only once or that might feed on animals that have eaten the bait.”  More specifically, the half-life of warfarin is 42 hours, whereas brodifacoum is 180 days.

The refined Warfarin used today is a different form than that used in earlier 1970s testing. Kaput products are manufactured with a purified and more effective form of warfarin that does not include impurities present in previous forms of the active.  Warfarin remains the most commonly used blood thinner today for human patients – prescribed to 30 million.

Research shows that Chicago Norway Rats are not first-generation resistant. Norway Rats from Chicago, which were originally thought to be first-generation resistant, had a 100% mortality rate with .025% Warfarin found in Kaput products.  What was thought to be a genetic resistance is likely due the vitamin K produced by the rats’ intestinal flora.  Vitamin K1 is an antidote for all anticoagulant actives.

Kaput® products, formulated with Warfarin and other first-generation anticoagulants, provide effective solutions to your rodent challenges while remaining the lower-risk to non-target animals.