Chlorfenapyr is a pyrrole pro-insecticide. Chlorfenapyr increases respiratory activity in German cockroaches when used at concentrations ranging from 1 to 10 µg per insect but has no effect on respiration in Sf9 cells when used at concentrations ranging from 1 to 100 µM and does not affect respiration in isolated rat liver mitochondria up to a concentration of 10 µM.