Indorex household flea spray contains a combination of 3 ingredients pyriproxyfen permethrin and piperonyl butoxide permethrin is an insecticide which effectively and quickly kills adult fleas present in a pets environment piperonyl butoxide is a synergist that reinforces the activity of permethrin pyriproxyfen is a long acting insect growth regulator that prevents flea eggs and larvae from developing into adults this breaks the flea life cycle and provides a continuous protection for up