Aromatherapy Versus Oral Ondansetron for Antiemetic Therapy Among Adult Emergency Department Patients: A Randomized Controlled Trial

Study Objective: We compare aromatherapy with inhaled isopropyl alcohol versus oral ondansetron for treating nausea among emergency department (ED) patients not requiring immediate intravenous access. Methods: In a randomized, blinded, placebo-controlled trial, we enrolled a convenience sample of adults presenting to an urban tertiary care ED with chief complaints including nausea or vomiting. We randomized subjects to 1 of 3 arms: inhaled isopropyl alcohol and 4 mg oral ondansetron, inhaled isopropyl alcohol and oral placebo, and inhaled saline solution placebo and 4 mg oral ondansetron. The primary outcome was mean nausea reduction measured by a 0- to 100-mm visual analog scale from enrollment to 30 minutes postintervention. Secondary outcomes included receipt of rescue antiemetic medications and adverse events. Results: We enrolled 122 subjects, of whom 120 (98.3%) completed the study. Of randomized subjects, 40 received inhaled isopropyl alcohol and oral ondansetron, 41 received inhaled isopropyl alcohol and oral placebo, and 41 received inhaled saline solution placebo and oral ondansetron. The mean decrease in nausea visual analog scale score in each arm was 30 mm (95% confidence interval [CI] 22 to 37 mm), 32 mm (95% CI 25 to 39 mm), and 9 mm (95% CI 5 to 14 mm), respectively. The proportions of subjects who received rescue antiemetic therapy in each arm were 27.5% (95% CI 14.6% to 43.9%), 25.0% (95% CI 12.7% to 41.2%), and 45.0% (95% CI 29.3% to 61.5%), respectively. There were no adverse events. Conclusion: Among ED patients with acute nausea and not requiring immediate intravenous access, aromatherapy with or without oral ondansetron provides greater nausea relief than oral ondansetron alone.