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Indoxacarb is the only commercialised oxadiazine insecticide. Although more correctly, indoxacarb is a pro-insecticide, which, when metabolised to its active form is a highly potent voltage dependant sodium channel blocker, acting on insects' nerves. The symptoms of insect intoxication include a rapid and irreversible cessation of feeding and the gradual onset of paralysis and death. Indoxacarb is metabolised to its active form rapidly in some insects, but at a much slower rate in other organisms, which results in favourable differential toxicity to non-target organisms. As such, Indoxacarb has been designated by the U.S. Environmental Protection Agency (EPA) as a "reduced-risk" pesticide in some use patterns.
In insects, indoxacarb is primarily active via ingestion, where it is absorbed and metabolised or "bio-activated" to the active form via specific hydrolase enzymes which remove a carbomethoxy group from the parent molecule. In mammals, the décarbométhoxylation of indoxacarb is much less efficient, and it is primarily metabolised to non-toxic compounds via different metabolic pathways.
A number of insecticides bind to and inhibit the sodium channel on insects' nerves, e.g. the pyrethroids and DDT. However, the N-decarbomethoxylated indoxacarb metabolite binds to a different site on the sodium channel, so insects that have developed target site resistance to pyrethroids or DDT do not show cross resistance to Indoxacarb. The Insecticide Resistance Action Committee (IRAC) has classified all insecticides by their mode of action. Insecticides that are included in the same mode of action group are likely to show cross resistance, and shouldn't be used together in an insecticide resistance management programme....