A randomized trial of loading vancomycin in the emergency department.

Background: Optimizing vancomycin dosing may help eradicate bacteria while avoiding resistance. The guidelines recommend loading doses; however, there are no data to demonstrate that this may result in a more rapid achievement of therapeutic troughs.

Objective: To evaluate the percentage of troughs reaching therapeutic levels at 12, 24, and 36 hours following an initial vancomycin dose of 30 mg/kg compared with 15 mg/kg.

Methods: This prospective, randomized study was performed in a community academic medical center. Patients who were to receive vancomycin in the emergency department were randomized to an initial traditional dose of 15 mg/kg or a 30-mg/kg loading dose followed by 15 mg/kg every 12 hours for 3 doses. Patients weighing >120 kg or with creatinine clearances <50 mL/min were excluded.

Results: In total, 99 patients were enrolled; 12 hours after the initial dose of vancomycin, there was a significantly greater proportion of patients reaching target trough levels of 15 mg/L among the patients who received a loading dose as compared with a traditional dose (34% vs 3%, P < 0.01). This trend continued at 24 hours but was not statistically significant. At 36 hours, there was no difference in the percentage of patients reaching target levels between the 2 groups. No statistically significant difference in nephrotoxicity or adverse events among the 2 groups was demonstrated.

Conclusion: A loading dose of 30 mg/kg of vancomycin achieved a higher percentage of therapeutic levels at 12 hours when compared with the traditional dose of 15 mg/kg, without increased nephrotoxicity or adverse events.