Topical drug delivery systems in the form of patches are convenient, attractive, and easy to use. Lidocaine is a very popular patch available on the United States market today. Accurate determination of the rate and extent of drug release and absorption is crucial to ensure the safety of individuals using these and other types of patches. The drug delivery rate can be determined early in the development process by using in vitro skin flux permeation studies, and later in humans by accurately quantifying residual drug from patches post-wear and in pharmacokinetic studies. In this study the investigators will employ two types of evaluation to determine the rate and extent of drug release and absorption from lidocaine patches, namely residual drug analysis post-wear and pharmacokinetic analysis in healthy adult volunteers. In addition, the investigators will compare the serum drug concentrations following patch and intravenous administration in order to determine the absolute bioavailability of these patches. Positive outcomes of this project will identify appropriate methods to determine the rate and extent of drug release and absorption from topical patches, and will help regulatory agencies in the development of Guidances for Industry regarding the characterization of drug release and absorption kinetics to ensure the safety of individuals utilizing these types of products.