Hospitalisation associated with use of the synthetic cannabinoid K2

To evaluate the proportion of patients hospitalised in an acute psychiatric ward associated with use of the synthetic cannabinoid K2, along with their clinical features.

Retrospective audit. K2 use was based on self-report.

Seventeen patients had a total of 21 admissions during between January and April 2013; this represented 13% of all admissions to the ward during this time. This was a first hospitalisation for 4 patients. Of the 13 patients with previous psychiatric hospitalisation, 9 patients had recurrences of pre-existing disorders, and 4 patients presented new psychotic symptoms. Presenting symptoms were variable, and included psychotic (paranoia, thought disorder, disorganised behaviour), affective (anxious, depressed) disturbances, and/or intense suicidal thinking/behaviour. Mean duration of admission was 8.5 days, with significantly longer durations for those presenting with psychotic symptoms (13.1 vs 4.4 days).

In this case series, use of K2 was associated with significant psychotoxicity requiring hospitalisation, and indicates substantial risk associated with use of synthetic cannabinoids.