Updated

It may be called fake weed, but Spice differs from the real stuff in at least two notable ways: Customary urine drug tests can't detect it, which the Guardian reports is leading more Americans to turn to it for an "undetectable" high—and that high can kill.

Some 8,000 Spice poisonings were reported in the US last year, which the Guardian calls "one of the drug's most damaging years since its introduction to the United States almost a decade ago." In one suspected case, a Mississippi man died after taking a single toke.

Indeed, potency is hard to predict and "the risk of overdosing is high," reports the Las Cruces Sun-News, which explains that because Spice is typically sold (at gas stations, for instance) as "herbal incense" that is labeled as not for consumption, it's out of the purview of the FDA and USDA.

Consumer Reports looks at the science: some type of leafy product is sprayed with chemicals, which include a synthetic cannabinoid. Pot's THC binds only partially with brain cells, but synthetic cannabinoids bind completely and can be up to 200 times stronger.

Of the almost 8,000 poisonings from synthetic cannabinoids reported last year, New York claimed 1,729, while Mississippi reported 1,362 with 17 suspected deaths. Overdose symptoms include kidney failure, stroke, irregular heartbeat, violent outbursts, and paranoia, and the Guardian notes that the screening limitations mean confirmed cases typically occur only when epidemiologists get involved.

(Some call Spice the "most dangerous" drug in America.)

This article originally appeared on Newser: He Took One Puff of Synthetic Pot. It Killed Him

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