Split Face Study of the Duration of Local Anesthetics

This is a research study to compare how long injectable pain medications (anesthetics) commonly used in dermatologic surgery are effective for. This study will compare a short-acting anesthetic, lidocaine with epinephrine, to one of two long-acting anesthetics (ropivacaine or bupivacaine). This study will also directly compare the duration of actions of ropivacaine and bupivacaine. The investigators hypothesize that the duration of anesthesia of short-acting anesthetics will not differ significantly from long-acting anesthetics at a single site and there will not be a significant difference between the two long-acting anesthetics at a single site.