The purposes of this study were to (a) evaluate the effect of pancreatic extract administered to patients with chronic pancreatitis and recurrent abdominal pain in a placebo-controlled, double-blind crossover study, (b) investigate the effects of acute intraduodenal pancreatic enzyme perfusion on pancreatic secretion, and (c) assess the effect of chronic, noninterrupted pancreatic extract administration on basal and stimulated pancreatic secretion. These studies demonstrated that pancreatic extract decreases abdominal pain and that intraduodenal perfusion with proteases but not with amylase or lipase suppresses pancreatic exocrine secretion in patients with chronic pancreatitis. Chronic administration of pancreatic extract to patients with chronic pancreatitis decreased both basal and stimulated pancreatic exocrine secretion.