INTRODUCTION: Droperidol is a dopamine-2 receptor antagonist in the class of butyrophenone antipsychotics with antiemetic, sedative, analgesic, and anxiolytic properties. In the postoperative setting, droperidol provides an opioid sparing effect and decreases nausea/vomiting. Another butyrophenone antipsychotic, haloperidol, has been shown to reduce morphine milliequivalents (MME) administered when used for abdominal pain in the emergency department (ED). The purpose of this study is to evaluate if the use of droperidol for undifferentiated abdominal pain reduces the amount of MME administered in the ED. METHODS: This retrospective, single-center study included patients ≥18 years old who presented to the ED for undifferentiated abdominal pain. Patients must have had two separate encounters for abdominal pain, one encounter where they received droperidol and one encounter where they did not receive droperidol but did receive an opioid. The primary outcome was the difference in MME administered between the two separate patient encounters. Secondary outcomes included utilization rates of rescue antiemetics, rescue analgesics, admission to the hospital, hospital length of stay, and adverse effects (including arrhythmias and extrapyramidal symptoms). RESULTS: Fifty patients with self-matched encounters were evaluated. A majority of the patients were female (33/50, 66 %) with a median age of 38 years old. All doses of droperidol were intravenous and the majority of patients received a dose of 2.5 mg (34/50, 68 %
range 1.25-5 mg). Non-droperidol encounters received significantly more MME compared to droperidol encounters (19.4 MME [IQR 12-30] vs 10 MME [IQR 0-20], p-value 0.0002). There were no statistically significant differences between the secondary outcomes. CONCLUSION: Among patients presenting to the ED for abdominal pain, droperidol administration resulted in a significant reduction in MME administration. Future research should include prospective studies, comparison of droperidol to haloperidol, and investigate droperidol use beyond the ED for these encounters.