The effect of semax and mexidol on the course of acute pancreatitis in rats was studied in comparison with the action of contrical, fluorouracil, and dibunol. It was established that a single intraductal or intraperitoneal administration of semax or mexidol markedly reduces the loss of experimental animals (to 10-13%), decreases hyperfermentemia, lipid peroxidation activation, and vascular permeability, improves microcirculation, and accelerates healing of the damaged pancreatic zones by substitutional repair of pancreatic acini not accompanied by coarse fibrous changes in the parenchyma. Upon the intraductal administration, semax and mexidol were more effective than contrical, fluorouracil, and dibunol.