Since Thursday, 15 New Yorkers -- all residents of Harlem and Chelsea -- have been checked into local emergency rooms after suffering from nausea, dizziness, hallucinations and other adverse effects caused by smoking fake pot.
"K2, Spice, Green Giant -- no matter what you call it, synthetic cannabinoids are dangerous and illegal," Health Commissioner Dr. Mary Bassett said in an official statement.
"I urge people not to use these products, which have caused a huge spike in emergency room visits this year."
According to city health officials, synthetic marijuana-related ER visits are up 220 percent in 2014.
Despite a 2012 law banning the sale of faux weed, health officials say leftover inventory still crops in mom-and-pop bodegas. At the time it was typically sold as "potpourri," crushed dried flowers with a scented intoxicant sprayed on the leaves and pedals.
"We really want to just warn New Yorkers that these are dangerous and illegal and not to buy them and also to report if they see them in stores," Dr. Denise Paone with the city's Department of Health and Mental Hygiene told CBS New York.
"Their compounds are changed frequently, so it's very hard to keep up with what's being put out there, but they're very dangerous."