Synthetic marijuana: What is it, how does it work, and is it dangerous?

Marijuana is generally considered one of the least harmful illicit drugs. But synthetic marijuana, the label given to a group of manufactured drugs derived from pot's cannabinoids, couldn't be any more different — and in recent months it's fostered a growing sense of concern among public health officials.

Synthetic drugs have inspired some public alarm in recent years. Synthetic bath salts caused a widespread panic when they were blamed for a 2012 attack in which a man chewed off another man's face in Miami, although it later turned out the attacker wasn't on any synthetic drugs. That year, Congress passed a law restricting the possession, purchase, and sales of synthetic drugs, following multiple warnings about the substances by the Drug Enforcement Administration and the National Institute on Drug Abuse. Recent surveys found synthetic drugs are some of the most popular illicit substances among high school students.

Now there's a new wave of alarm — this time about synthetic marijuana. In August, New Hampshire Governor Maggie Hassan declared a state of emergency after synthetic marijuana was linked to 44 overdoses. In 2013, the drug was linked to three deaths and at least 76 emergency visits at hospitals in the Denver area and Colorado Springs.

Is the panic warranted? From its name to effects to legality, many of the details about synthetic marijuana remain shrouded in misinformation and uncertainty — and public health officials worry the lack of education could enable deaths and overdoses. Here's a guide to how worried you should be.

1) What is synthetic marijuana?

A packet of synthetic marijuana. (Susannah Bryan / Sun Sentinel via Getty Images)

For one, it's not marijuana. Synthetic marijuana, also marketed under brand names like Spice and K2, is actually a broad category of synthetic cannabinoids produced in laboratories that attempt to mimic THC, the psychoactive compound in marijuana.

"Marijuana is a plant," said Andrew Monte, a medical toxicologist at the University of Colorado Denver-Anschutz Medical Center who previously wrote about the drug. "This is certainly not marijuana, nor is it really meant to be marijuana."

Synthetic cannabinoids are often marketed as "legal highs," but the federal government classified most of the chemicals used to produce them as schedule 1 substances, making it illegal to buy, sell, or possess anything containing the chemicals, even though it's still sold in some stores around the country.

Still, the Monitoring the Future survey in 2013 found that synthetic marijuana is the second most used illicit drug, after marijuana, among 10th graders and the third most used, after marijuana and amphetamines, among 12th graders.

2) What are some of synthetic marijuana's effects?

Public health officials are worried synthetic marijuana could lead to brain damage. (Matt Cardy / Getty Images News)

Synthetic marijuana gets users high, obviously, but it may have all sorts of horrifying side-effects, including nausea, vomiting, agitation, seizures, unusually fast heartbeat, unusually slow heartbeat, and, potentially, brain damage and strokes.

The drug's effect on the brain's cannabinoid receptors, which produce the high one feels after consuming real pot, can be 50 to 1,000 times stronger than traditional marijuana, according to Monte. The stronger interaction can produce a much more potent high, but it can also lead to the various health problems caused by synthetic marijuana.

Part of the risk is that users almost never know and can't predict what's actually in synthetic marijuana products. "If you test different packages with the same brand, over time there's different molecules in them," Monte said.

Some of these risks may be perpetuated by the drug's name. Tod Burke, a criminal justice professor at Radford University in Virginia who wrote about synthetic marijuana for the FBI, said synthetic marijuana's label is dangerously misleading, because it implies the drug is as safe as real pot. "It can lead to death," Burke said. "I don't know of any people who have overdosed on marijuana."

3) Is synthetic marijuana legal?

A stack of synthetic marijuana products in New Zealand. (Jason Oxenham / Getty Images News)

Since the federal government prohibited the most common chemicals found in synthetic marijuana, it technically isn't legal to buy, sell, or possess for consumption.

In the past, manufacturers and vendors avoided a ban by changing up their formulas with new chemicals — before different levels of government could regulate and ban them. But Monte said that's no longer an issue after the federal government classified the most popular synthetic cannabinoids as schedule 1 substances.

Instead, manufacturers and vendors package the drugs as incenses or aromatherapy products, often alongside labels that claim the drugs aren't for human consumption. The clever packaging lets sellers skirt laws and the oversight that would otherwise prohibit sales, Monte explained.

"One of the major issues is the manpower of law enforcement," Monte said. "You can't necessarily go into every shop in the street and look at every product that's hanging there and say, 'Okay, I'm going to take this off, and we're going to send it off for testing.'"

4) When was synthetic marijuana invented?

Synthetic marijuana was meant for testing on lab animals, not consumption by people. (China Photos / Getty Images News)

In the 1990s, John Huffman, a retired researcher from Clemson University, created some of the chemicals used in synthetic marijuana to study their effects on lab animals' cannabinoid receptors. "These receptors don't exist so that people can smoke marijuana and get high," Huffman told the Los Angeles Times in 2011. "They play a role in regulating appetite, nausea, mood, pain, and inflammation."

Huffman insisted synthetic cannabinoids were never meant for human consumption, and he previously suggested only "idiots" would use the drug to get high. "These things are dangerous — anybody who uses them is playing Russian roulette," Huffman told the Los Angeles Times. "They have profound psychological effects. We never intended them for human consumption."

But that hasn't stopped critics from blaming Huffman for the consequences now linked to the drug. "It's become a royal pain in the rear end," Huffman told the Los Angeles Times. "I had a TV station in Moscow accuse me of trying to poison America's youth."

In recent years, synthetic marijuana products have also gone through multiple iterations of new development. The latest generations of the drug are much more physiologically active, Monte said, making them more potent but also more dangerous.

5) Would people use synthetic marijuana if pot were legal?

Could legalizing this stop synthetic marijuana? (Seth McConnell / Denver Post via Getty Images)

Under current legalization proposals, pot is only legal for adults 21 and older under the current legalization proposals, so teens, an age group in which synthetic marijuana is very popular, could still seek it out. Synthetic marijuana, in fact, continues to crop up in Colorado even though real pot is now legally sold in retail outlets. Synthetic pot is also one way to use drugs without testing positive on most drug tests, which some employers would likely still use even if pot were legal. (Drug test evasion is one reason synthetic marijuana is so popular in the military, according to Monte.) Of course, others could seek out synthetic marijuana just because it's a different kind of drug than actual marijuana. "Why do people use methamphetamine when marijuana is legal?" Monte said. "I would argue the same thing. It's not because marijuana is illegal that they use methamphetamine."

But in a 2013 CNN column, Jag Davies of the Drug Policy Alliance argued that the only way to make synthetic marijuana go away is fully legalize pot. The argument is very common among critics of the war on drugs and supporters of marijuana legalization: If people could access marijuana legally, they wouldn't need to resort to synthetic marijuana for a legal high.

"Almost no one would touch this synthetic stuff - actually, it wouldn't even exist - if it weren't for the criminalization of the marijuana plant itself," Davies wrote. "Attempting to ban one new substance after another is like a game of whack-a-mole: each time one gets banned, another untested and potentially more dangerous drug pops up to replace it."

6) Is the ability to buy synthetic weed online making it more of a problem?

Bitcoins were used on Silk Road to buy synthetic drugs. (George Frey / Getty Images News)

Internet marketplaces, such as the now-defunct Silk Road, have allowed people to buy synthetic weed online, causing its use to spread. These online shops not only make the drugs more accessible, but they can also let users purchase the substances anonymously.

"We're going to continue to see this type of thing," Monte said. "Whether it's synthetic cannabinoids or these quote-unquote 'bath salts,' … we will continue to see this stuff because of the ease of the internet marketplace and because it's always an opportunity to make money."

The Monitoring the Future report also blamed the internet for the increased circulation of synthetic drugs: "The spread of such new drugs appears to be facilitated and hastened today by young people's widespread use of web-based social networks. We predict a continuous flow of such new substances onto the scene, and believe that the task of rapidly documenting their emergence, establishing their adverse consequences, and quickly demystifying them will remain an important means by which policymakers, researchers, and educators deal with the continuing threats posed by such drugs."

7) What are states and the federal government doing about synthetic marijuana?

New Hampshire Governor Maggie Hassan and others leave the White House. (Brendan Smialowski / AFP via Getty Images)

The Drug Enforcement Administration in 2011 classified synthetic cannabinoids as schedule 1 substances, effectively banning them. Congress made the classification permanent with the Synthetic Drug Abuse Prevention Act of 2012.

The classification allowed law enforcement to go after the substance and its vendors. In May, the DEA reportedly busted an international drug ring that sold synthetic marijuana. "This is the most significant synthetic drug investigation ever conducted by the Denver field division of DEA and is part of an ongoing international operation conducted by DEA," Barbra Roach, a special agent in charge of Denver's DEA office, told the Denver Post. "This is cutting edge. It is something our labs are seeing for the first time."

Some states have also acted on their own. Several states banned synthetic marijuana even before the DEA acted in 2011. New Hampshire Governor Hassan in August declared a state of emergency over the drug, allowing public health officials and law enforcement to investigate stores and prevent the drug's sale.

But the moves haven't stopped synthetic marijuana products from appearing in grocery stores and gas stations around the country.

Monte said public health officials and law enforcement should do more to coordinate anti-drug efforts and educate the public on synthetic marijuana's risks.

"There are laws on the books that can help get rid of it," Monte said. "But if people don't recognize it and don't report it and don't message to the public that this is something that's dangerous, then there really won't be any changes."

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