The drug of choice for local anesthesia in most emergency departments is lidocaine. However, it wears off shortly after suturing is complete and patients may experience pain after closure of the wound. We conducted a study to determine the degree of anesthesia obtained during and after repair of lacerations using lidocaine 1% versus bupivacaine 0.25%, a long-acting local anesthetic. Lidocaine and bupivacaine were administered in a double-blind, randomized fashion to 104 patients. Each patient was asked to rate his pain on a 0 to 10 scale (0, no pain; 10, severe pain) prior to administration of the anesthetic. They then rated pain on an identical scale at 30 minutes, and one, two, three, four, five, six, 12, 18, and 24 hours after completion of suturing. The mean baseline pain was 2.96 for the lidocaine group and 3.07 for the bupivacaine group. This decreased to less than 1.0 in both groups 30 minutes after infiltration. It remained low for the bupivacaine group for the next five hours, but increased almost to preanesthesia levels by two hours in the lidocaine group. A three-way analysis of variance revealed a significant difference (P less than .001) between the pain response of the two groups. There was no statistical difference (P greater than .05) between the age of the patients, size of laceration, and amount of drug used. The study shows that patients do experience pain after a wound is sutured and the anesthetic has worn off. It also demonstrates that bupivacaine significantly reduces the pain a patient may experience after repair of a wound.