METHODS: We analyzed syndromic surveillance data reported by all 60 Oregon EDs during March–October 2015. To identify CRAEs, chief complaint and clinical impression fields were queried for cannabis terms. We categorized records as physical symptoms (e.g. palpitations, vomiting), psychogenic symptoms (e.g. anxiety, paranoia), or injury (e.g. fall), and excluded those mentioning cannabis incidentally (e.g. “denies marijuana use”) or with insufficient information.
RESULTS: “Marijuana,” “THC,” “cannabis,” “smoke pot,” “brownie,” “smoke weed,” and “hash” retrieved 168 records from >1 million visits; 130 (77%) were for CRAEs and 38 (23%) were excluded, for 11.9 CRAEs per 100,000 visits. Patients’ median age was 29 years (range: 0–80 years); 33 (25%) were <21 years. More visits were for psychogenic symptoms (53; 41%), physical symptoms (43; 33%) or both (12; 9%) than for injuries (8; 6%). None were hospitalized. Cannabis was the only substance in 88 CRAEs (68%); alcohol was the most common concomitant substance (19; 15%). Cannabis-only users were more likely than multiple substance users (50% vs 29%) to report physical symptoms (RR 1.75, p=0.02). Visits did not increase after July 1st (p=0.25).
CONCLUSIONS: Cannabis-related adverse events are infrequently reported. Most CRAEs are for toxicity (physical and psychogenic symptoms) rather than injury. Although no increase was observed yet, evolving cannabis use patterns warrant ongoing surveillance with more widespread cannabis availability in Oregon.