Really weird question.. but the answer is Chloroform.
unconscious
a zombie will fall down if struck on the head, but will not get knocked unconscious.
The spelling is unconscious (knocked out).
The likely word is "unconscious" (knocked out).
Well, if he knocked the president unconscious, then he's called a "criminal".
George W. Bush.
George Bush
yes you can be knocked out without a concussion
Thomas jefferson
Unconscious people, whether they are asleep, knocked out, or anesthetized, continue to breathe. A person who is not breathing will be dead in not more than 5 minutes under normal circumstances (not counting the use of such things as hyperbaric oxygen chambers, and other special circumstances).
5-10 milliseconds
16