The Frenchman decided to remain on the field despite getting knocked out from a collision with Everton forward Romelu Lukaku during yesterday's goalless draw at Goodison Park.
"Andre Villas-Boas was wrong," Warnock told talkSPORT. "I think in this particular case it should have been taken out of his hands.
"If anything had happened to him and he gets an accidental knock on the brain, you do not know what the consequences are.
"We're talking about life and death here, it's not double vision, this is a serious knock. You can't mess about [with things like that]."
Brain injury charity Headway have accused Tottenham of being "irresponsible" in allowing Lloris to continue playing.