I just spoke to a customer service representative from Raid. I had sprayed a house centipede on my family room ceiling with a can of "Raid Ant & Roach" and it dropped and vanished. She said the can of "Raid Ant & Roach" will kill it. She said they don't list centipedes on the can because there are too many insects to list and house centipedes are in the same family as silverfish, which they do list. But, when I asked how long it would take to die, she said it is hard to say. Maybe very soon or maybe by the end of the day...