Experimental haemorrhagic pancreatitis was induced in 12 piglets by infusing Nataurocholate trypsin into the pancreatic duct with simultaneous intravenous secretin stimulation. Within some minutes after the infusion all animals developed severe pancreatitis accompanied by the production of bloody ascites. Unless given specific treatment the pigs died within 24 h. Of the animals treated with xylocaine infusion (50 microgram/kg/min for 24 h) one died within 24 h, one during the second day, and four lived for over a week, at which time they were killed. Although xylocaine treatment signficantly improved the survival of the animals, it did not seem to influence the local damage of the pancreatic tissue. Xylocaine has been shown to inhibit phospholipase-A in vitro. It is possible that xylocaine also acts in vivo by inhibiting phospholipase-A, thus preventing lethal tissue damages at an early stage of pancreatitis.