Evidence-Based Reviews

Cannabis, synthetic cannabinoids, and psychosis risk: What the evidence says

Current Psychiatry. 2011 September;10(9):49-58

References

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34. Dresen S, Ferreirós N, Pütz M, et al. Monitoring of herbal mixtures potentially containing synthetic cannabinoids as psychoactive compounds. J Mass Spectrom. 2010;45(10):1186-1194.

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37. Hurst D, Loeffler G, McLay R. Synthetic cannabinoid agonist induced psychosis: a case series. Presented at: 164th Annual Meeting of the American Psychiatric Association; May 14-18, 2011; Honolulu, HI.

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In the most recently presented case series of patients without pre-existing psychosis (N = 10), symptoms resolved in 70% of patients within 8 days, but 30% had psychosis that persisted beyond 5-month follow-up.³⁷ Collectively, these reports suggest that synthetic cannabinoid intoxication is associated with acute psychosis as well as exacerbations of previously stable psychotic disorders, and also may have a propensity to trigger a chronic psychotic disorder among vulnerable individuals.

Clinical Point

The FDA has placed 5 synthetic cannabinoids on Schedule I, but there are hundreds of synthetic cannabinoid homologues

Because of health concerns and the abuse potential of herbal incense products, many have been banned in several European countries, 18 U.S. states, and the U.S. military.^33,38 In March 2011, the FDA placed 5 synthetic cannabinoids (JWH-018, JWH-073, JWH-200, CP-47,497, and cannabicyclohexanol) on Schedule I, making them illegal to possess or sell in the United States.³⁸ However, there are hundreds of synthetic cannabinoid homologues, and herbal incense manufacturers have rapidly adapted by substituting other synthetic cannabinoids not yet banned by existing legislation.³⁴ The effects of these newly arising compounds in humans, including their psychotic potential, are largely unknown.

Table 2

Herbal incense products and synthetic cannabinoids

Herbal incense brand names	Cannabinoids they may contain
Spice, K2, Mojo, Aroma, Dream, Chill, Chaos, Sence, Smoke, Skunk, Space Diamond, Silent Black, Genie, Algerian Blend, Yucatan Fire, Tai Fun, Sensation, SpicyXXX, Spike 99, Bonsai-18, Banana Cream Nuke, Wicked X, Natures Organic, Zen	JWH-018, JWH-019, JWH-073, JWH-167, JWH-250, JWH-253, JWH-387, JWH-398 CP-47,497; cannabicyclohexanol HU-210, HU-211 AM-694

Table 3

Case reports of psychosis associated with synthetic cannabinoids

Study	N (age)	Herbal product or suspected cannabinoid	Previous psychotic disorder	Symptoms
Müller et al, 2010^a	1 (25)	JWH-018 “Spice”	Yes	Anxiety, exacerbation of paranoid delusions, delusions of control, auditory hallucinations
Vearrier et al, 2010^b	1 (17)	JWH-018	No	Tachycardia, hypokalemia, agitation, visual hallucinations
Every-Palmer, 2010^c	5	JWH-018 CP-47,497	Yes	Agitation, disorganization, paranoid and grandiose delusions
Rodgman et al, 2011^d	3	JWH-018 (“Mojo”)	–	“Mojo psychosis”
Benford et al, 2011^e	1 (20)	JWH-018 (“Spice”)	–	Tachycardia, anxiety, paranoia, auditory and visual hallucinations
Van Der Veer et al, 2011^f	3 (20 to 30)	“Spice” “Spike 99”	No	Anxiety, disorganization, paranoia, Capgras delusion
Every-Palmer, 2011^g	9 (20s to 40s)	JWH-018 (“Aroma”)	Yes	Anxiety, agitation, paranoia
Hurst et al, 2011^h	10 (21 to 25)	“Spice”	No	Anxiety, agitation, confusion, disorganization, paranoia, ideas of reference, hallucinations
Source: References a. Müller H, Sperling W, Köhrmann M, et al. The synthetic cannabinoid Spice as a trigger for an acute exacerbation of cannabis induced recurrent psychotic episodes. Schizophr Res. 2010;118(1-3):309-310. b. Vearrier D, Osterhoudt KC. A teenager with agitation: higher than she should have climbed. Pediatr Emerg Care. 2010;26(6):462-465. c. Every-Palmer S. Warning: legal synthetic cannabinoid-receptor agonists such as JWH-018 may precipitate psychosis in vulnerable individuals. Addiction. 2010;105(10):1859-1860. d. Rodgman C, Kinzie E, Leimbach E. Bad Mojo: use of the new marijuana substitute leads to more and more ED visits for acute psychosis. Am J Emerg Med. 2011;29(2):232. e. Benford DM, Caplan JP. Psychiatric sequelae of spice, K2, and synthetic cannabinoid receptor agonists. Psychosomatics. 2011;52(3):295. f. Van Der Veer N, Friday J. Persistent psychosis following the use of Spice. Schizophr Res. 2011;130(1-3):285-286. g. Every-Palmer S. Synthetic cannabinoid JWH-018 and psychosis: an explorative study. Drug Alcohol Depend. 2011. [Epub ahead of print]. h. Hurst D, Loeffler G, McLay R. Synthetic cannabinoid agonist induced psychosis: a case series. Presented at: 164th Annual Meeting of the American Psychiatric Association; May 14-18, 2011; Honolulu, HI

Related Resources

Murray RM, Morrison PD, Henquet C, et al. Cannabis, the mind and society: the hash realities. Nat Rev Neurosci. 2007;8(11):885-895.
European Monitoring Centre for Drugs and Drug Addiction: Synthetic cannabinoids and “spice.” www.emcdda.europa.eu/publications/drug-profiles/synthetic-cannabinoids.
U.S. Department of Justice, Drug Enforcement Agency, Office of Diversion Control: Schedules of controlled substances: temporary placement of five synthetic cannabinoids into Schedule I. www.deadiversion.usdoj.gov/fed_regs/rules/2011/fr0301.htm.