STUDY OBJECTIVE: To compare oral transmucosal fentanyl citrate (OTFC) with IM meperidine, promethazine, and chlorpromazine (MPC) for conscious sedation of children. METHODS: This prospective, randomized, single-blinded study involved a convenience sample of 40 children, 3 to 8 years of age, who presented to an urban pediatric emergency department and required laceration repair. Patients were premedicated with either OTFC (10 to 15 micrograms/kg) and a mock injection or intramuscular MPC (2 mg/kg meperidine, .5 mg/kg promethazine, and .5 mg/kg chlorpromazine) followed by a placebo lozenge. RESULTS: Both OTFC and MPC caused significant reductions in activity scores at 15 to 75 minutes after medication administration. Although the MPC group was more sedated, there was no difference between groups in Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) scores during the laceration repair or in the suturing physician's assessment of sedation quality (rated excellent or good for 75% and 69% of OTFC and MPC groups, respectively). Two children (both in the OTFC group) had oxygen saturation levels of less than 95% but required only transient supplemental oxygen. Other adverse events were common but not serious; they differed between groups in type but not number, with vomiting in 45% of the OTFC group and prolonged somnolence in 37% of the MPC group. Mean time to discharge was 99 minutes, with no difference between groups. CONCLUSIONS: Both medications reduced activity significantly. Although MPC caused deeper sedation, the medications had comparable effects on patient behavior during the repair and yielded comparable ratings of physician satisfaction. Large numbers of nonserious adverse events occurred in both groups.