This is a phase III/IV, randomized, placebo-controlled, patient-blinded cross-over pilot study to evaluate the effectiveness of Amisulpride in the treatment and prevention of Post Operative Nausea and Vomiting (PONV) in adult patients, 18-65 years of age, at a single surgery site in the pacific northwest who are undergoing bariatric surgery. Approximately 100 patients will be randomized in a 1:1 ratio to receive a single intravenous dose of Amisulpride (5mg IV single dose) or a placebo (saline control, 1mL IV single dose) at the induction of anesthesia. Those who initially receive placebo will undergo an additional randomization in the post-anesthesia care unit (PACU) to receive a dose of Amisulpride (10mg IV single dose) or placebo (saline control, 2mL IV single dose) in a 1:1 ratio as first line treatment for PONV.
