ANTISECRETORY EFFECTS OF 3-OMEPRAZOLE REGIMENS FOR MAINTENANCE TREATMENT IN DUODENAL-ULCER

This study was carried out to assess the antisecretory effects and the ir possible changes over time of three different dose regimens of omep razole that could be proposed for maintenance treatment in duodenal ul cer. Forty-five patients with endoscopically proven duodenal ulcer wer e studied by means of 24-hr gastric pH-metry both in basal conditions and on the fifth day of acute treatment with omeprazole 20 mg in the m orning. Ulcers healed after four weeks (in three cases after eight wee ks) and afterwards, 15 patients were randomized to receive orally at 0 800 hr in single-blind fashion omeprazole 10 mg daily (group A), 15 to receive omeprazole 40 mg on Saturday and Sunday followed by a five-da y period without medication (group B), and 15 to receive omeprazole 20 mg every other day (group C) for up to three months. On the 20th and 80th days of these maintenance treatments 24-hr gastric pH-metry was r epeated to assess the antisecretory effectiveness of each regimen over a two-month period. In patients of group B these tests began at 1700 hr on Friday, the last of live days off treatment, and in those df gro up C at 1700 hr of the day off medication. All three dose regimens of omeprazole were able to raise pH values significantly (P < 0.01-0.001) compared to basal levels. Omeprazole 20 mg every other day was more e ffective (P < 0.01) than omeprazole 40 mg weekend, but did not differ significantly from omeprazole 10 mg daily. The durations of acid inhib ition (pH > 3.0 units/24 hr) were 12.44, 10.00, and 17.38 hr with grou ps A, B, and C, respectively. There was no significant difference betw een the pH profiles of the 20th and 80th days with every dose regimen. It is concluded that all three dose regimens of omeprazole are effect ive in reducing gastric acidity and their pharmacodynamic action does not change with time. Therefore they are suitable to be assessed in la rge clinical trials aimed at verifying the prevention of duodenal ulce r recurrence for longer periods.