This week, over 30 people in NYC were hospitalized after apparently accidentally overdosing on a substance known as "K2," reports Fox News . K2 is just one of many mysterious and widely misunderstood substances that supposedly provide a legal cannabis-like high. And their recent rise in popularity highlights yet another need for some serious discussion of our current drug policies. Here's everything you need to know about so-called "synthetic marijuana" products:K2, also known as "spice" or "scooby snax" are "synthetic marijuana" products, meaning they're not made from actual cannabis. But they are often — incorrectly — purported to produce a similar high. The active ingredients in the products are actually usually chemical liquids, but they may be sprayed on dried herbs to give a more cannabis-like feel.These products were once legally sold in bodegas and corner stores in New York, but the state outlawed this in 2012 after a rise in emergency-room visits related to the drug, The New York Times reports. But K2 products are still legally available in many states across the country and are often labeled as "herbal incense" or "potpourri" with packaging saying "not for human consumption" as a way to get around regulation, according to the Office of National Drug Control Policy . Most of them originate from Asia and are smuggled into the U.S. under different labels, per the Drug Enforcement Agency.Very little research has been done on the way these products affect the brain, so researchers aren't totally sure what's up. But we do know there are some big differences here that users might not be aware of.Marijuana gets us high because a few of its chemical compounds (the most well-known being THC and CBD) bind to cannabinoid receptors in our brains. Although synthetic marijuana products can bind to these receptors, they do so in a different way — they may bind to different cannabinoid receptors than those favored by THC, for example. Or they may bind to those receptors way more readily than THC does, potentially producing stronger unpleasant effects.Because so little is known, it's hard to say exactly what the risks are. But that's another risk in itself. These products aren't tightly regulated, so users don't always know what they're getting — or in what doses — and may end up unprepared for what they do get.And it seems like, when things go bad, they can go really bad: As of last April , there were 1,500 synthetic-marijuana-related hospitalizations reported in the U.S. And the Centers for Disease Control and Prevention (CDC) have seen multiple serious kidney issues in people who needed emergency care after using synthetic marijuana products.First off, although headlines may make it seem like these products are everywhere, relatively few people are actually using them in the U.S. And, perhaps unsurprisingly, a 2013 global study found that 93% of those who tried synthetic marijuana vastly preferred the real thing.Still, people looking for a legal high in the wake of our country's restrictive drug policies may turn to synthetic marijuana when they can't get their hands on the real stuff. Synthetic marijuana products also have the added benefit of not showing up on routine drug tests. So while they're not exactly popular, it's not totally surprising that they're gaining popularity.