S1143 Retrospective Analysis of Anti-Emetics Used for Cannabis Hyperemesis Syndrome to Assess Efficacy of Abortive Medications

Introduction: Cannabis hyperemesis syndrome (CHS), a cannabis-induced subtype of cyclic vomiting syndrome (CVS), is characterized by recurrent, acute-onset vomiting in chronic cannabis users, often relieved by hot showers. The American Gastroenterological Association recommends abortive treatments such as topical capsaicin, haloperidol, benzodiazepines, promethazine, olanzapine, and ondansetron based on existing evidence. However, standard anti-emetics like ondansetron and promethazine are often the only medications used in clinical practice. This study evaluates trends in anti-emetic use and infers treatment efficacy based on hospital length of stay. Methods: We conducted a retrospective observational study of adult patients admitted to a multi-hospital network in Southeast Michigan from 2018 to 2023 with a diagnosis of cannabis hyperemesis syndrome. Pregnant patients with hyperemesis were excluded. Extracted variables included demographics, medications used, length of stay, and comorbidities such as major depressive disorder, irritable bowel syndrome, and type 1 and type 2 diabetes mellitus. Descriptive statistics were used to summarize medication usage patterns. Results: Of 2,812 patient encounters, the mean age was approximately 31 years, with 56% male and 44% female patients. Ondansetron was the most commonly administered anti-emetic (60.8%), followed by promethazine (38.7%), lorazepam (12.8%), haloperidol (11.2%), olanzapine (9.1%), and topical capsaicin (7.9%). Tricyclic antidepressants were used in only 1.1% of encounters. Comorbidities included major depressive disorder in 17.5% of patients, type 2 diabetes mellitus in 4.2%, type 1 diabetes mellitus in 2.5%, and irritable bowel syndrome in 2.2%. Notably, 20.4% of patients had 2 or more encounters, indicating a high rate of recurrent hospitalizations. The overall median length of stay was 2 days (interquartile range 1–3). Those who received topical capsaicin had a median stay of 1 day. Patients treated with haloperidol, lorazepam, ondansetron, and promethazine had a median stay of 2 days, while those receiving olanzapine and tricyclic antidepressants had median stays of 2–3 and 3 days, respectively. Conclusion: Standard anti-emetics remain the most commonly used therapy, while only a small percentage of patients received medications such as topical capsaicin or haloperidol, as recommended by existing guidelines. This study highlights gaps in awareness of evidence-based therapies and the need for prospective studies to guide management.