Nineteen patients with postoperative enterocutaneous fistulae were randomised, in a double blind fashion, to receive either 12 days of octreotide (100 micrograms tds) by subcutaneous injection or 12 days of placebo injections. Fistula output for 7 days before and during all 12 days of treatment was recorded for each patient. Fistula losses before entering the trial were similar for both the placebo group (n = 8; range of daily medians: 202 mls to 400 mls) and the group of patients randomised to receive octreotide (n = 11; range of daily medians: 252 mls to 550 mls). There was no significant difference in fistula output between the two groups of patients while receiving either 12 days of placebo injections or 12 days of subcutaneous octreotide therapy. Fistula closure, defined as no fistula output for 2 successive days during the 12 days "therapy" period, was seen in only 1 patient given octreotide and in 3 patients given the placebo. In a double blind prospective study of 19 patients with enterocutaneous fistulae, octreotide therapy was neither associated with a significant reduction in fistula losses nor an increased rate of spontaneous fistula closure.