S394 INTRODUCTION: Postoperative vomiting (POV) in children undergoing eye muscle surgery continues to cause patient discomfort and unanticipated hospitalization. [1] Despite many strabismus/POV studies, there are few prospective studies incorporating controls dealing with this issue. We sought to document the incidence of immediate and delayed POV in this population, both in the absence of antiemetic pretreatment and following pretreatment, with either droperidol, promethazine, or ondansetron. METHODS: Following institutional approval and parental informed consent, 104 healthy children for strabismus surgery, ages 3-12 years, were enrolled in the study. Randomization and drug preparation was done by a pharmacist and administered by anesthesiologists blinded to drug group. The anesthetic inductions were either by mask or IV means and the patients were intubated following muscle relaxants or deep inhalation anesthesia. Maintenance was with inhaled agents. Propofol was not used. During anesthesia, patients received intravenously either droperidol 75 mcg/kg (Group 1), promethazine 0.5 mg/kg (Group 2), ondansetron 100 mcg/kg (Group 3), or saline controls (Group 4). Acetaminophen and/or opioids were used perioperatively as needed. Initial POV was assessed by the PACU nursing staff and subsequently by clinic staff on POD #1. Data were analyzed using ANOVA, CHI Square, and unpaired t tests. RESULTS: 102 completed the protocol (Table 1). The four groups were comparable with respect to age, sex, and opioid usage. The incidence of immediate POV in the control group was 36%. In the droperidol and ondansetron group, the incidence was 11% and 12% respectively. No patients vomited in the immediate post-op period in the promethazine group. The difference among the 3 drugs and control was significant (p=.0031). There was no significant difference among any of the 3 drugs. Delayed vomiting after discharge occurred in 33% of the saline group, 44% of the ondansetron group, 15% of the droperidol group, and 8% of the promethazine group. These differences were not significant (p=.46). There were no significant differences in discharge time from the PACU.Table 1CONCLUSIONS: These results support the work of Blanc, et al [2] which showed promethazine to be an effective antiemetic in this type of surgery in children. Promethazine was at least as effective as either droperidol or ondansetron in our study. Since there were no significant differences in discharge times, promethazine appears to be equally effective as droperidol or ondansetron for control of post-op emesis in strabismus patients at our institution. Our cost for ondansetron 4 mg is $16.70; for droperidol 5 mg $.90; for promethazine 25 mg $.39. The cost savings are obvious. Supported in part by grant "Research To Prevent Blindness" #70-260-2256