Cannabinoid Hyperemesis Encounters After Medical Legalization in Oklahoma.

Introduction Medical cannabis has recently become legal in Oklahoma. Cannabinoid hyperemesis syndrome (CHS) is severe nausea, vomiting, and often abdominal pain typically seen in heavy users of cannabis. The aim of this study is to determine whether emergency department (ED) diagnoses of CHS have increased after medical legalization. Methods We performed a retrospective chart review study of equivalent time periods prior to and after the first legal sales of medical cannabis in Oklahoma. Data were gathered from a single urban ED of adult patients with diagnosed or suspected CHS. We analyzed data using a chi-square analysis of CHS cases as a proportion of total ED visits. Results Diagnosed and suspected CHS visits increased from 43 cases in the eight months preceding the first legal sale to 62 cases in the eight months after legalization. This represents a statistically significant increase in ED visits for CHS (p = 0.026). Total ED encounters were 30,437 and 28,362, respectively, during those time periods. The proportion of visits for CHS was much higher (220/100000 vs 13.3/100000) than previously reported in the literature. The pre-legalization and post-legalization groups did not differ by age, sex, history of GI illness and diabetes, pregnancy, or other drug use. Conclusion We observed a statistically significant increase in ED visits for CHS after the first legal sales of medical cannabis in Oklahoma. Our high proportion of ED visits for CHS could be related to study design, increased provider awareness, high THC levels in Oklahoma's medical cannabis, or increased numbers of cannabis users after legalization. Increases in ED visits for CHS and other cannabinoid-related illnesses must be weighed against the positive effects for cannabis users by policymakers.