EFFICACY OF LONG-TERM THERAPY WITH LOW-DOSES OF OMEPRAZOLE IN THE CONTROL OF GASTRIC-ACID SECRETION IN ZOLLINGER-ELLISON SYNDROME PATIENTS

Thirteen patients with Zollinger-Ellison syndrome were investigated: 8 without, and 5 with, previous gastric surgery. After 7-34 months of t reatment with famotidine, 8 out of 13 patients were resistant to this drug. Omeprazole 60 mg/day was administered to these 8 patients; after one month, the dose was reduced to 40 mg/day, and after another month to 20 mg/day. Basal acid secretion was inhibited by every dose of ome prazole. The patients were then treated with a low dose (20 mg/day) of omeprazole for a longer period. Periodic clinical and endoscopic asse ssments, and measurement of basal acid secretion showed the efficacy o f this low dose of omeprazole in our Zollinger-Ellison syndrome patien ts. The drug was discontinued after 12-32 months of omeprazole treatme nt, and gastric acid recovery was evaluated. Four patients recovered 5 0 % of their 'initial basal acid secretion' after 5 days, while two pa tients who had been treated with omeprazole for a longer time (30-32 m onths) recovered only 38 and 40%, respectively, of their 'initial basa l acid secretion' at the tenth day. Our results indicate that the omep razole dosage to be used in the treatment of Zollinger-Ellison syndrom e must be chosen principally on the basis of basal acid secretion dete rmination. A low daily dose of omeprazole is able to control acid secr etion in Zollinger-Ellison syndrome for a long period (10-30 months). The slow recovery of gastric secretory function demonstrates the prolo nged inhibitory effects of omeprazole.