How Pyrethrum Works

Pyrethrum affects the central nervous systems of all types of flying and crawling insects, blocking nerve junctions so that nervous impulses fail, and the insect dies. In the lowest concentrations, pyrethrum affects insect behavior producing a so called ‘avoidance reaction’ which results in the insect fleeing the source of the chemicals. Importantly, pyrethrum, inhibits normal biting behavior in female mosquitoes, making them unable to seek their usual blood meals.

At slightly greater concentrations, pyrethrum makes insects lose usual behavioral patterns. This means they abandon their hiding places and come out into the open, bringing them into contact with larger quantities of pyrethrins which soon knock them down and kill them.

More about how it works