Buffered versus plain lidocaine as a local anesthetic for simple laceration repair. STUDY OBJECTIVE: Buffered lidocaine was compared with plain lidocaine as a local anesthetic for simple lacerations. DESIGN: Randomized, double-blind, prospective clinical trial. SETTING: Urban emergency department. TYPE OF PARTICIPANTS: Ninety-one adult patients with simple linear lacerations were enrolled. Patients with allergy to lidocaine and patients with an abnormal mental status were excluded. INTERVENTIONS: Each wound edge was anesthetized with either plain or buffered lidocaine using a randomized, double-blind protocol. The pain of infiltration was measured with a previously validated visual analog pain scale. MEASUREMENTS AND MAIN RESULTS: Analysis of pooled data and paired data (using patients as their own controls) revealed that infiltrating buffered lidocaine was significantly less painful than plain lidocaine (P = .03 and P = .02, respectively). There was no significant difference in the anesthetic effectiveness of the two agents during suturing. CONCLUSION: Buffered lidocaine is preferable to plain lidocaine as a local anesthetic agent for the repair of simple lacerations. 