There's been a surge or cockroach in my house lately, always found them in my house. Perhaps they crawled in due to my broken toilet floor trap.
I then buy this, Baygon Cockroach Control as my current ones are meant more to kill ants and mosquitoes. Its quite effective, a direct spray on even adult roach makes them paralyzed almost instantly.
Sure enough, when I returned home, there's a roach crawling around. I gleefully tested my new "weapon", and sure enough, the cockroach turned on its back.... struggling with its feet on the air.
I smirked, now I know how those mad world war scientist felt when they tested toxic on human.