AUDIE CORNISH, HOST:
For more on K2 and to get a better sense of exactly what this substance is, we turn to Dr. Kathryn Hawk. She's assistant professor of emergency medicine at the Yale School of Medicine in New Haven. She joins us now. Welcome to the program.
KATHRYN HAWK: Thanks so much for having me.
CORNISH: So these synthesized chemicals are known by a number of different things on the street - K2, spice, synthetic marijuana. Describe what exactly is in it.
HAWK: So one of the problems with the overdoses that we've seen, and with K2 and these synthetic cannabinoids, is that honestly it's very difficult to tell what they are actually made of and which substances are there. And that's one of the challenges - is when you think that you're buying K2, you're not sure what you're getting.
CORNISH: What you're looking at is dried leaves sprayed with industrial chemicals, right?
HAWK: Correct. They could be sprayed with any number of chemicals.
CORNISH: Help us understand. If K2 is synthetic, where does it come from, right? Like, who's pumping it out? Is it something that you make in a factory, in a house?
HAWK: So what we know about these synthetic cannabinoids and K2 is that they're made in these kind of clandestine laboratories that are predominantly overseas. I can't tell you exactly where they come from. But they don't represent, in any way shape or form, something that is kind of diverted from a pharmaceutical company or anything along those lines.
CORNISH: This is not the first time we've seen a mass overdose, right? In New York City, there was a batch of overdoses a few years ago. How widespread is the use of this kind of drug in the U.S.?
HAWK: It's difficult to track in part because substances like K2 and synthetic cannabinoids actually don't show up in your toxicology testing. And so some of the more traditional ways we have for kind of understanding who's using these substances are not as sure. So what I can tell you is that this is certainly something that we see regularly in our emergency department at Yale New Haven Hospital. We do see it on a daily basis. But usually it's, you know, one or two versus, you know, dozens, as we saw yesterday.
CORNISH: And we know people at this point do buy it over-the-counter - right? - often at small neighborhood stores.
HAWK: Sure. And that's actually been one of the challenges with synthetic cannabinoids - and bath salts also - is that initially the regulations around restricting drugs as Schedule 1 substances was drug and structure specific. And these new analogs were coming along faster than could be regulated or legislated. And so there's been challenges with keeping up, so to speak, with regulations around trying to keep these drugs illegal and limit their sale.
CORNISH: That was my next question because I thought at least some 40 states had laws banning it.
HAWK: So in the past several years, they have increased cracking down on these types of chemicals and structures. But they're still certainly out there and still available.
CORNISH: Dr. Kathryn Hawk is an assistant professor of emergency medicine at the Yale School of Medicine. Thanks for speaking with us.
HAWK: Sure, happy to.
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