Effect of octreotide acetate on pancreatic exocrine function.

Somatostatin and its analogs have been shown to inhibit both pancreatic endocrine and exocrine function. We hypothesized that octreotide acetate (Sandostatin), a somatostatin analog, decreases the pancreatic flow rate through a peptide-mediated mechanism and alters pancreatic fluid composition by inhibiting carbonic anhydrase action and circulating peptide levels. To test this hypothesis, we collected pancreatic fluid from six patients (four with pancreatic fistulas and two with pancreatic drains after pancreatic resection). Pancreatic fluid volume and chloride, sodium, potassium, amylase, lipase, and bicarbonate levels were measured before and after octreotide acetate therapy. Octreotide acetate reduced pancreatic fluid output by a mean of 75 percent (p less than 0.05), increased chloride concentration by 21 percent (p less than 0.05), and reduced bicarbonate content by 45 percent (p less than 0.05). Sodium levels were unchanged, but the potassium concentration was increased by 14 percent (p less than 0.05). Total amylase and lipase production per 24 hours was decreased by 63 percent and 27 percent, respectively (differences not significant). Somatostatin may be useful in the treatment of established pancreatic fistulas and may be a useful prophylactic tool to prevent postoperative fistula formation.