system
Given the following post, respond as if you're commenting on Reddit:
human
What do roach sprays and barrier sprays actually DO to roaches to kill them?

As I'm sitting in my living room, I can see a roach on my porch in the throes of death, on its back, kicking and writhing.  It'll probably do that for another half hour or so, and then finally kick the bucket.  But what is it dying of, specifically?  Asphyxiation?  Some nervous system shutdown?
gpt
Many bug sprays contain pyrethrin family compounds which mess with the nervous systems in most insects by preventing the resetting of their nerves. Once tensed, muscles cannot relax so the bug basically siezes up. Larger vertibrates have sufficient enzymes to inactivate these compounds before they can affect our nervous system.