Mild pancreatitis is a common complication of endoscopic retrograde cholangio-pancreatography (ERCP) and endoscopic sphincterotomy. Knowing that a bolus injection of natural somatostatin (SRIF) dramatically reduces pancratic secretion, a study was conducted in 33 subjects undergoing invasive diagnostic procedures. A placebo (n = 16) or SRIF (n = 17; 4 µg/kg) were injected before cannulation. Enzymatic rise was observed in 16 (94 %) subjects receiving placebo and in 8 (50%) injected previously with SRIF. In the former group 65% reported abdominal pain whereas only 19% had this complaint in the SRIF series. Results suggest that a bolus injection of SRIF may attenuate pancreatic irritation caused by diagnostic procedures or sphincterotomy.