Apparently, some kinds of cocaine use result in overheating, so the perps strip down. The cannibalism is an oddity, and if he took multiple shots while still eating, I'm not ruling out George Romero's involvement.
I found another version of this story and it's said the drug was LSD. I wonder what Timothy Leary would think about his wonder drug.
"To those with the entitlement mentality: You are only entitled to what you put into life, not what you expect to get out of it."-Yours Truly