The effect of long-acting somatostatin analogue on enzyme changes after endoscopic pancreatography. The effect of the long-acting somatostatin analogue, octreotide acetate (Sandostatin) on enzyme elevation after endoscopic pancreatography was studied in a prospective, randomized, double-blind trial. Sixty-three consecutive patients undergoing ERCP were randomly allocated to two group. In the control group, 34 patients received isotonic sodium-chloride, and in the treated group 29 patients received 0.1 mg of octreotide acetate subcutaneously before the pancreatography. After the endoscopy, amylase levels increased to pathological range in 15 of the controls and in 3 of the treated patients, whereas lipase levels showed a pathological rise in 17 of the controls and in 5 of the treated patients. A significant difference (p less than 0.01) was observed in the amylase and lipase changes between the two groups at 90 and 180 min after pancreatography. The enzyme levels showed at 90 min, mean +/- SD amylase: controls 540 +/- 185 units/liter, treated patients 261 +/- 108 units/liter; lipase: controls 304 +/- 98 units/liter, treated patients 198 +/- 88 units/liter. These findings suggest that the use of long-acting somatostatin analogue ameliorates the enzyme increases in the serum after endoscopic pancreatography. 