K2, Summit, and Spice: Fake ‘weed’ is not so nice

April 1, 2011

The latest drugs of abuse — marketed as herbal incense or aromatherapy blends under brand names like K2, Summit, and Spice — deliver a high reportedly similar to that induced by 9-tetrahydrocannabinol, the psychoactive cannabinoid found in marijuana. Early clinical reports, however, associate these synthetic cannabinoids with more extreme symptoms, such as agitation, paranoia, hallucinations, and seizures. There also have been several deaths associated with K2 product use.

Recreational drug users, including first-time drug users, seem to be attracted to these agents because they skirt existing regulations and avoid detection in common drug-screening programs. Yet, the potential for toxicity, addiction, and secondary effects, such as impaired driving, make these compounds a serious medical and public-health concern. Moreover, forensic data show that these herbal products are sometimes laced with numerous synthetic cannabinoids, all of which have varying degrees of toxicity, so users never know what they are getting.

Despite package labeling indicating “not for human consumption,” these products are being ingested or smoked at increasing rates. In 2010, U.S. poison-control centers recorded 2,882 calls related to the use of K2-type products. As recognition increases, exposure cases are expected to rise; more than 700 calls to the poison-control center have been recorded in the first two months of 2011.1

To address this public-health threat, a translational-science research group formed by the Arkansas Department of Health-Public Health Laboratory (ADH-PHL) has developed an assay that detects and measures JWH-018, JWH-073 — two of the more popular synthetic cannabinoids identified in products seized in Arkansas (and thought to be more potent than 9-tetrahydrocannabinol) — and various oxidized metabolites of each. The validated assay has been in use for research purposes since the spring of 2010. It employs liquid chromatography tandem mass spectrometry and uses authentic standards. The assay provides high sample throughput and can be run in less than eight minutes with minimal sample preparation. The new assay has applicability for clinical, forensic, and public-health labs investigating a host of outstanding medical and epidemiological questions. What are the clinical symptoms of JWH-018 and JWH-073 use and overdose? Is one more toxic than the other? Are certain patient groups more susceptible to toxicity? Are synthentic cannbinoids metabolized differently by different people? How does metabolism influence clinical symptoms and analytical detection?

The ADH-PHL workgroup — which includes the Arkansas State Crime Laboratory; University of Arkansas for Medical Sciences, Colleges of Medicine, Pharmacy and Public Health; Arkansas Children’s Hospital; Centers for Disease Control and Prevention; U.S. Drug Enforcement Agency, and several private entities — has collected several hundred human-urine specimens as part of an ongoing biomonitoring program aimed at determining use and prevalence in Arkansas. The workgroup also has begun to correlate clinical symptoms with analytical results and to use in vitro and in vivo mice models to study the pharmacology, toxicology, and metabolism of K2-type products. Knowledge gained through this translational workgroup is being used to develop educational and community-outreach programs aimed at reducing injuries and deaths related to these emerging drugs of abuse.


  1. American Association of Poison Control Centers. E-mail correspondence. February 24, 2011.

Laura James, MD, is section chief of Clinical Pharmacology and Toxicology at Arkansas Children’s Hospital and professor of Pediatrics in the College of Medicine at the University of Arkansas for Medical Sciences.
Jeffrey H. Moran, PhD, is branch chief of Environmental Chemistry at the Arkansas Department of Health, Public Health Laboratory, and a research instructor in the College of Medicine at the University of Arkansas for Medical Sciences, Department of Pharmacology and Toxicology.
Cindy Moran, BS, is the quality assurance manager at the Arkansas State Crime Laboratory.
Keith R. McCain, PharmD, CSPI, is an assistant professor in the College of Pharmacy at the University of Arkansas for Medical Sciences, Department of Pharmacy Practice, all located in Little Rock, AK.

This work was supported, in part, by the Association of Public Health Laboratories [Grant Innovations in Quality Public Health Laboratory Practice] (JHM), Centers for Disease Control and Prevention [Grant U90/CCU616974-07 and contract 200-2007-21729] (JHM). In addition, this work was supported by a pilot grant awarded to LPJ through the Arkansas Center for Clinical and Translational Research which is funded by the National Center for Research Resources [1 UL 1RR029884, Curtis Lowery, PI].