THURSDAY, Nov. 11 --(HealthDay News) -- A form of synthetic marijuana known as "K2" is sending young people to the hospital with racing heart beats, extreme anxiety and hallucinations, toxicologists warn.
In recent months, physicians and toxicologists say more young people have been showing up in emergency rooms after smoking synthetic marijuana. Despite the side effects, K2 is legal in many states, although many state legislators are rushing to pass legislation banning it.
Since the start of 2010, the American Association of Poison Control Centers has received nearly 2,000 reports of people who became ill after smoking K2, compared to about a dozen in 2009. Poison control officials described some of the symptoms as "life-threatening."
K2 is often marketed as incense and sold in packets of herbs laced with synthetic marijuana at "head shops," gas stations, convenience stores and online for about $30 to $40 per three-gram bag. The drug also goes by other names, including Spice, Spice Gold, Spice Diamond, Yucatan Fire, Solar Flare, K2 Summit, Genie, PEP Spice, and Fire n Ice, according to the U.S. Drug Intelligence Center.
While people who smoke K2 think they're going to experience deep relaxation and euphoria, those who end up in the hospital report unpleasant experiences, said Dr. Anthony Scalzo, medical director of the Missouri Poison Center and chief of toxicology at St. Louis University.
"The classic symptoms are agitation, anxiety, racing heart beat, elevated blood pressure," Scalzo said. "And some kids are having very negative psychotropic experiences. One said, 'I felt like I went down to hell'."
In some cases, the drug also causes vomiting, tremors and seizures, according to federal drug abuse agencies.
Scalzo was the first to sound the alarm about K2 earlier this year after seeing a couple of dozen of reports of young people treated at emergency rooms who said they'd smoked K2.
The drug, also sold under the name Happy Shaman Herbs, Smoke, Skunk and Zohai, among others, was developed for study purposes in the mid-'90s in the lab of John Huffman, a Clemson University chemist, who was conducting National Institute on Drug Abuse-supported research on cannabinoids.
The chemical makeup of the drug, which he called JWH-018 and JWH-073, was similar to tetrahydrocannabinol (THC), the active ingredient in marijuana, only considerably more potent.
While THC is a cannabinoid, it's one of many, Huffman said. There are many other substances that interact with the cannabinoid receptors in the brain and other organs, Huffman said.
"These receptors don't exist so that people can smoke marijuana and get high; they play a role in regulating appetite, nausea, mood, pain and inflammation. They may be involved in the development of conditions such as osteoporosis, liver disease and some kinds of cancer," Huffman said. "Synthetic cannabinoids can help us understand these interactions and ultimately this knowledge may contribute to the development of new therapies.
Huffman and his colleagues described JWH-018 and JWH-073 in scientific literature. "Evidently some people have figured out how to make them," Huffman said.
Huffman warned that the drugs were only meant to be used in the lab and were not designed for use in people, Huffman said. "These compounds were not meant for human consumption," Huffman said. "Their effects in humans have not been studied and they could very well have toxic effects. They absolutely should not be used as recreational drugs."
And while the makers of K2 seem to have latched on to JWH-018, many other labs have developed their own synthetic cannabinoids that may also find their way into synthetic marijuana products, Scalzo said.
The K2 craze caught on several years ago Europe, prompting several countries to make synthetic cannabis products illegal.
In the United States, the Drug Enforcement Agency has listed K2 as a "drug or chemical of concern." But because it isn't officially "scheduled," it remains legal under federal law, according to published reports.
Alarmed by the rise in popularity, several states have rushed to outlaw K2. Earlier this year, Kansas became the first state to ban K2. Other states that have outlawed it include Iowa, Missouri, Arkansas, Kentucky, Alabama, Michigan and Illinois (where K2 remains legal until the end of the year). There are similar bills pending in many other states, including Nebraska, North Dakota, Ohio, New York, New Jersey and Louisiana.
Scalzo said the prohibitions don't come a moment too soon. Little is known about the health effects of the drug. But he's heard enough anecdotal reports about strange behavior -- ranging from extreme agitation to withdrawal to a suicide after smoking K2 -- to be concerned.
"This chemical was not meant to be used in any kind of pharmaceutical manner," Scalzo said.
The U.S. National Institute of Drug Abuse has more about synthetic THC.