Buffered lidocaine has been recently recommended for local anesthesia, as there is less pain on injection of the buffered solution. Reduced pain on injection of lidocaine and epinephrine buffered to a neutral pH was confirmed in 20 subjects (P less than .01). Concentrations of buffered lidocaine and epinephrine were performed in order to evaluate their stability. Buffered lidocaine dropped to 66.1% of initial concentrations after 4 weeks when stored at 25 degrees C. Buffered epinephrine fell to 1.34% of its initial concentration under similar conditions. Buffered lidocaine and epinephrine maintained 94.54% and 82.04%, respectively, of their initial concentrations after 4 weeks when refrigerated at 0-4 degrees C. Both lidocaine and epinephrine maintained greater than 90% concentration 2 weeks after buffering when stored at 0-4 degrees C. This permits batch buffering of lidocaine with epinephrine and storage for periods up to 2 weeks when properly refrigerated.