Authorities said they suspected the attacker was under the influence of bath salts. The victim is in critical condition at a Miami hospital.
Not the same substance used to scent your bathwater, bath salts contain amphetamine-like chemicals such as methylenedioxypyrovalerone (MDPV) and are sold as "cocaine substitutes" or "synthetic LSD." Its effects include paranoia, hallucinations, convulsions and psychotic episodes.
"This is a terrible drug because it takes a combination of methamphetamine, and the paranoia and the aggressiveness, and LSD, the hallucinations, and PCP, the extreme paranoia that you get, combines it into one, and has unpredictable effects on human behavior," Paul Adams, an emergency room doctor in Miami, told CNN.
The drug remains legal in some states, although many others have taken steps to ban the substances.
But sometimes, when one chemical used in bath salts is banned, another chemical is substituted to skirt the law, said attorney Alex Manning.
"People are making this stuff out of household products, stuff that's in their kitchens," she said.
It can take "five or six grown men" to restrain a bath salts user, she said. "It's PCP on crack."
And cases are on the rise, Adams said.
Police in Panama City, Florida, said last year they had seen two violent incidents linked to use of bath salts. In one, a woman allegedly tried to behead her 71-year-old mother; in the second, a man on bath salts used his teeth to tear up the back seat of a patrol car.
Sharp said he never felt the urge to "eat anybody's flesh" while under the influence of bath salts, but noted, "You feel like you're 10 feet tall and bulletproof, and you actually do not feel any pain."
