The purpose of this study was to investigate the effect of a single treatment of high voltage pulsed current (HVPC) on edema formation. Twenty-four frogs were anesthetized, and both hind limbs of each frog were traumatized by impact. Limb volumes were measured by water displacement immediately before and after trauma and at predetermined intervals for 24.0 hours posttrauma. One limb of each frog was randomly selected to receive 30 minutes of continuous, 120-pulse per second, cathodal HVPC at voltages 10% less than motor threshold levels. Data were analyzed by an analysis of variance for repeated measures. Sources of significant differences were determined by paired t tests (probability values determined by Bonferroni adjustment). A single 30-minute application of HVPC significantly curbed edema formation for between 4.0 and 7.5 hours following treatment (ie, volumes of treated limbs were significantly less than those of untreated limbs). These results suggest that regimens currently applied to humans (ie, one treatment per day or three times per week) may be insufficiently aggressive to provide sustained treatment effects.