A designer drug known to be 85 times more potent than marijuana has been identified as the cause for the mysterious, "zombielike" mental state that afflicted several New Yorkers this past summer.

In July, emergency workers in Brooklyn responded to reports of several people becoming severely intoxicated and showing a high degree of altered mental status after smoking a synthetic drug.

Eighteen of the 33 individuals who showed such symptoms were rushed to the hospital for emergency treatment.

While the exact cause of the overdose was not immediately known to investigators, researchers say that they have finally pinpointed the culprit drug after testing the blood and urine samples of the victims.

AMB-FUBINACA

In a study featured in the New England Journal of Medicine, researchers discovered that victims took in a synthetic cannabinoid known as AMB-FUBINACA. This drug was originally developed by Pfizer but was never tested on humans and production was later abandoned.

Since it was not known what the victims took at the time, the term "synthetic marijuana" was used to refer to the possible cause. However, researchers say this is dangerously misleading for the public.

"There is this false idea out there that these drugs are safe, because no one overdoses on marijuana," study co-author Roy Gerona from the University of California, San Francisco said.

According to a report by the New York Times, the synthetic drug that was used in Brooklyn was commonly referred to the users as AK-47 24 Karat Gold. Laboratory tests showed that this drug was 85 times more potent than tetrahydrocannabinol (THC), the main agent in marijuana.

Some illegal drug manufacturers prefer to use synthetic cannabinoids over the plant-based THC because of their different chemical structure.

Chemical compounds used to make these forms of drugs are often produced using research conducted by universities and pharma companies. They are also difficult to detect and regulated when they make it to the market.

Gerona said people who take these synthetic drugs do not show any signs of usage when they are tested, making them more appealing than other forms of illegal drugs.

Gerona and his colleagues traced the history of the drugs to a researcher in Clemson University named John W. Huffman. He was looking to develop a drug that could utilize the medicinal benefit of THC but without subjecting users to its psychotropic effects.

Huffman was able to produce more than 300 chemical compounds throughout the course of his work. He published his findings in academic literature.

In 2008, a synthetic drug compound known as "K2" in the United States and "Spice" in Europe soon appeared on the market. Its primary chemical agent, JWH-18, was named after Huffman.

JWH-18 soon spread across the United States and was later tagged as a Class 1 narcotic by authorities.

As for the drug used in the New York outbreak, Pfizer may have already stopped developing AMB-FUBINACA but the researchers believe drug labs in other countries may have gotten hold of the patent and used it to produce new forms of drugs.

The team said AB-FUBINACA is considered to be 50 times more potent than earlier forms such as K2. However, something must have gone wrong with the dosing when illegal drug makers tried to create their own mixture.

This resulted in a more powerful drug that can cause people to enter a trancelike state. Sufferers often groan and moan, with their eyes becoming lifeless and their movements becoming slow and mechanical.

Law enforcement has had a difficult time putting a stop to the manufacture and sale of synthetic drugs. Gerona said this is because whenever drug labs produce a new drug, they wait until it becomes scheduled by authorities and then they move on to developing a new compound.

While Gerona doesn't believe that drug dealers would intentionally kill their clients with their drugs, the continued production of synthetic compounds could increase health risks as they become even more potent.

"No compound that has been made yet has the potential to kill thousands of people," Gerona said. "But that is a scenario that is becoming more and more close to reality."