Intramuscular Droperidol versus Intramuscular Dimenhydrinate for the Treatment of Acute Peripheral Vertigo in the Emergency Department: A Randomized Clinical Trial

OBJECTIVE: The emergency department (ED) treatment of acute peripheral vertigo (APV) has not been well studied. The purpose of this study was to determine the efficacy of intramuscular (IM) droperidol vs IM dimenhydrinate, in the treatment of ED patients with APV. METHODS: The study was a randomized, double-blinded clinical trial, performed at a suburban, teaching ED. A convenience sample of adult patients with symptoms and signs consistent with rigid diagnostic criteria for APV were randomized to one of two treatment groups. Patients more than 65 years of age were excluded to reduce the likelihood of diagnostic misclassification. Demographic and historical features were recorded on a standardized data form. Patients recorded their initial level (t0) of discomfort on a 10-centimeter (cm) visual analog scale (VAS). Treatment group 1 received 2.5 mg droperidol IM, while treatment group 2 received 50 mg dimenhydrinate IM. After 30 minutes (t30), patients again recorded the severity of their symptoms on the VAS. Chi-square, t-tests, and Mann-Whitney were used for statistical comparison as appropriate. All tests were two-tailed, with alpha set at 0.05. Primary outcome parameters were the mean change in VAS score from t0 to t30, and the percentage of patients in each treatment group who felt well enough to go home after t30 without further ED intervention. RESULTS: There were 20 patients in the droperidol group and 20 in the dimenhydrinate group. The two groups were similar with respect to mean age (40 +/- 13 years droperidol vs. 42 +/- 13 years dimenhydrinate; p = 0.6), female sex (60% vs. 50%; p = 0.7), and mean median duration of symptoms [3 (interquartile range 2-12) vs 9 (interquartile range 2-30) hours; p = 0.2]. Mean initial t0 VAS scores were 7.2 +/- 2.3 and 7.8 +/- 1.9 (p = 0.47). Both treatment groups had mean reductions in VAS scores at t30 of 3.3 [95% confidence interval (95% CI) = 2.3 to 4.3]. At t30, 42% of patients in the droperidol group and 45% of patients in the dimenhydrinate group felt well enough to go home without further ED intervention. CONCLUSIONS: The authors found no difference between the therapeutic efficacies of IM droperidol and dimenhydrinate for the treatment of acute peripheral vertigo.