Sounds like a date rape drug.
http://www.cnet.com/news/arrests-made-over-zombifying-drug-known-as-devils-breath/
"It sounds like a scene from a spy movie. Two Chinese women, suspected of being members of an international Triad-like criminal group, persuade strangers walking down the street to inhale a mysterious powder they allege has curative powers. But the powder actually causes the victims to enter a zombie-like state and are made to lead their attackers to their homes, where they are summarily robbed.
While it might sound like fiction, this scene has allegedly taken place again and again in Paris, according to a report in the British newspaper The Telegraph....
Crimes related to the drug have been widely reported in Colombia and Ecuador, according to The Guardian, and the US's Overseas Security Advisory Council warns travelers visiting Columbia to beware of a scopolamine attack.
"Unofficial estimates put the number of annual scopolamine incidents in Colombia at approximately 50,000, says the agency's website. "It is most often administered in liquid or powder form in foods and beverages. The majority of these incidents occur in night clubs and bars, and usually men, perceived to be wealthy, are targeted by young, attractive women. "

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