The possible risk factors for failure of medical therapy were examined in 23 patients with pancreatic ascites or effusion. The ascites or effusion resolved completely in 10 patients after a mean (+/- SEM) of 30 +/- 2 days of conventional medical treatment. In five patients in whom conventional medical therapy failed, the addition of an octreotide (SMS 201-995) analogue to the medical therapy led to a resolution of the ascites (three patients) or effusion (two patients). Six patients underwent surgery after failed medical therapy, one patient died while receiving conservative therapy, and one patient refused hospital treatment. Serum sodium and albumin levels were significantly lower, and the ratio of total fluid protein to total serum protein was significantly higher in the group that failed to heal in response to conventional medical therapy. Nine of 11 patients with mild to moderately severe chronic pancreatitis healed in response to conservative therapy. Only one of 10 patients with advanced pancreatitis healed in response to conventional medical therapy. Our results suggest that a selective surgical approach is warranted to treat pancreatic ascites and effusion. In patients with mild or moderately severe pancreatitis, medical therapy is recommended. Patients with advanced pancreatic disease should be selected for early surgery. Octreotide may be useful in the patient in whom surgery may be associated with a prohibitive morbidity or mortality.