The pathophysiologic role of nocturnal acid secretion in gastric ulcers

Antisecretory effects of three omeprazole regimens for maintenance treatment in duodenal ulcer

This study was carried out to assess the antisecretory effects and their possible changes over time of three different dose regimens of omeprazole that could be proposed for maintenance treatment in duodenal ulcer. Forty-five patients with endoscopically proven duodenal ulcer were 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 morning. Ulcers healed after four weeks (in three cases after eight weeks) and afterwards, 15 patients were randomized to receive orally at 0800 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-day 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 repeated 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 five days off treatment, and in those of group 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 effective (P < 0.01) than omeprazole 40 mg weekend, but did not differ significantly from omeprazole 10 mg daily. The durations of acid inhibition (pH > 3.0 units/24 hr) were 12.44, 10.00, and 17.38 hr with groups A, B, and C, respectively. There was no significant difference between the pH profiles of the 20th and 80th days with every dose regimen. It is concluded that all three dose regimens of omeprazole are effective in reducing gastric acidity and their pharmacodynamic action does not change with time. Therefore they are suitable to be assessed in large clinical trials aimed at verifying the prevention of duodenal ulcer recurrence for longer periods.

A pharmacodynamic study of two omeprazole regimens suitable for long-term treatment of duodenal ulcer

BACKGROUND

The experience with long-term treatment of peptic ulcer with omeprazole is still scant, but the possibility cannot be excluded that its better pharmacodynamic effect on gastric acidity also has a positive result in the relapse rate. Moreover, this drug acts via a mechanism other than receptorial binding, and therefore its efficacy should not dissipate with time. This study was carried out to assess the pharmacodynamic properties and the possible changes with time of two dose regimens of omeprazole that could be suitable for long-term treatment in duodenal ulcer.

METHODS

Twenty patients with endoscopically proven duodenal ulcer were studied by means of 24-h gastric pH-metry both in basal conditions and on the 5th day of acute treatment with 40 mg omeprazole in the morning. All the ulcers healed after 4 weeks, and thereafter 10 patients were randomized to receive orally 20 mg omeprazole daily at 0800 h in single-blind fashion (group A) and 10 to receive 20 mg omeprazole every other day (group B) for up to 6 months. At the end of the 1st, 3rd, and 6th month of these maintenance treatments 24-h gastric pH-metry was repeated to assess the antisecretory effect of each regimen over time. In group-B patients the test was performed on 2 consecutive days (without and with medication) at each time interval. The fasting gastrin values were also determined. The patients underwent esophagogastroduodenoscopy every 2 months.

RESULTS

Three patients in group B were lost to follow-up for various reasons, and only seven remained eligible for final analysis. The two long-term regimens of omeprazole were able to increase significantly pH values (p < 0.02-0.001) and the times spent at and above pH 3.0 (p < 0.001) over 24 h compared with basal conditions. In group A the 24-h pH value obtained in the 6th month was higher (p < 0.02) than that in the 3rd month of maintenance treatment. In group B the pharmacologic effect tended to decrease on the day without medication compared with the day with medication, but the difference between them was significantly (p < 0.05) only at the 6-month interval. There was no significant difference between the gastrin levels of the two groups in the long-term treatment. No ulcer relapse was detected at any long-term endoscopic control in the two groups of patients.

CONCLUSIONS

The two omeprazole regimens we tested are effective in reducing gastric acidity, and their pharmacodynamic action does not decrease with time. They are therefore suitable for maintenance treatment in acid-related disorders.

Variability in individual response to various doses of omeprazole. Implications for antiulcer therapy

This study was carried out in order to perform a combined prospective assessment of the individual pharmacodynamic response and of duodenal ulcer healing in patients treated with three different doses of omeprazole. Ninety-nine patients with endoscopically proven duodenal ulcers were subdivided into three parallel groups of 33 cases, who were randomly assigned to receive orally at 0800 hr, in single blind fashion, either 10 mg, 20 mg, or 40 mg of omeprazole. All of them underwent continuous intragastric pH monitoring both in basal conditions and on the fifth day of each dose regimen; ulcer healing was then assessed endoscopically after four weeks of treatment. All three doses of omeprazole caused pH values to increase significantly (P < 0.001) over the whole 24-hr period. In patients treated with omeprazole 10 mg, the individual responses showed the highest variability: the acid inhibition, expressed in terms of time spent above pH 3.0, lasted for more than 16 hr in 42% of cases, for more than 8 hr in 28%, and for less than 6 hr in 30%. In patients treated with omeprazole 20 mg, the pharmacological response was more marked and uniform and lasted for more than 16 hr in 79% of cases; however, it is worth noting it lasted for less than 6 hr in three patients (10%). In patients treated with omeprazole 40 mg, the individual response was excellent (more than 16 hr) in 94% of cases, and it lasted for less than 6 hr in only one patient (3%).(ABSTRACT TRUNCATED AT 250 WORDS)