Omeprazole inhibition of nocturnal gastric secretion in patients with duodenal ulcer

Comparison of acid-lowering drugs for endoscopy negative reflux disease: Systematic review and network Meta-Analysis

BACKGROUND

The comparative efficacy and safety of medical therapies for gastro-esophageal reflux symptoms in endoscopy-negative reflux disease is unclear. We conducted a network meta-analysis to evaluate efficacy and safety of proton pump inhibitors (PPIs), histamine-2-receptor antagonists, potassium-competitive acid blockers (PCABs), and alginates in patients with endoscopy-negative reflux disease.

METHODS

We searched MEDLINE, EMBASE, EMBASE Classic, and the Cochrane central register of controlled trials from inception to February 1, 2022. We included randomized controlled trials (RCTs) comparing efficacy of all drugs versus each other, or versus a placebo, in adults with endoscopy-negative reflux disease. Results were reported as pooled relative risks with 95% confidence intervals to summarize effect of each comparison tested, with treatments ranked according to P-score.

KEY RESULTS

We identified 23 RCTs containing 10,735 subjects with endoscopy-negative reflux disease. Based on failure to achieve complete relief of symptoms between ≥2 and <4 weeks, omeprazole 20 mg o.d. (P-score 0.94) ranked first, with esomeprazole 20 mg o.d. or 40 mg o.d. ranked second and third. In achieving adequate relief, only rabeprazole 10 mg o.d. was significantly more efficacious than placebo. For failure to achieve complete relief at ≥4 weeks, dexlansoprazole 30 mg o.d. (P-score 0.95) ranked first, with 30 ml alginate q.i.d. combined with omeprazole 20 mg o.d., and 30 ml alginate t.i.d. second and third. In terms of failure to achieve adequate relief at ≥4 weeks, dexlansoprazole 60 mg o.d. ranked first (P-score 0.90), with dexlansoprazole 30 mg o.d. and rabeprazole 20 mg o.d. second and third. All drugs were safe and well-tolerated.

CONCLUSIONS & INFERENCES

Our results confirm superiority of PPIs compared with most other drugs in treating endoscopy-negative reflux disease. Future RCTs should aim to better classify patients with endoscopy-negative reflux disease, and to establish the role of alginates and PCABs in achieving symptom relief in both the short- and long-term.

In vivo effect of omeprazole on HLA-DR expression and the monocyte-macrophage function in patients with duodenal ulcer disease

It is not known if omeprazole possesses any action on immune system. Therefore, we examined the effect of omeprazole on parameters of cellular immunity [T-cell subsets-CD3+, CD4+, CD(8+)- and HLA-DR expression on peripheral blood lymphocytes (PBLs)] and on function of peripheral blood monocyte-macrophages (PBMMs) [random migration (RM), directed migration (DM), phagocytosis index (P-I) and HLA-DR expression] in 13 duodenal ulcer patients before and during 3-mo omeprazole treatment. The number of T-cell subsets varied at pretreatment values (p > 0.05), whereas the percentage of HLA-DR positive PBLs increased significantly after 3-mo therapy (p < 0.001). On the other hand, all studied parameters concerning PBMMs (RM, DM, P-I and HLA-DR expression) increased significantly after 3-mo therapy (p < 0.001, p < 0.001, p < 0.003, p < 0.001, respectively vs. baseline values). In conclusion, omeprazole exerts an immunopotentiating effect on functions of PBMMs and may also influence T-cell function. These effects can be considered as an advantage of omeprazole in long-term treated patients with peptic ulcer disease.

Concentration of refluxed acid and esophageal mucosal injury

The hallmark of gastroesophageal reflux disease (GERD) is an increase in esophageal exposure to gastric juice. This exposure can result in complications such as esophagitis, stricture, and Barrett's esophagus. The aim of this study is to determine if there are specific pH exposure patterns that are associated with the development of these complications. The 24-hour esophageal pH data for 50 normal subjects and 154 patients with proven GERD were analyzed for time spent at different pH intervals. Increased esophageal acid exposure at a given interval occurred when the cumulative time of exposure exceeded the 95th percentile of that measured in the 50 normal subjects for that interval. The greatest prevalence of mucosal damage was found in the those patients with increased esophageal exposure to pH 0 to 2, corresponding to the known pKa of pepsin. This exposure was not related to a hypersecretory state. In addition, mucosal injury was associated with an increased esophageal exposure to pH 7 to 8. We conclude that mucosal injury in patients with GERD is related to the exposure time to gastric juice with a pH of less than 2 or greater than 7.

Omeprazole 20 mg three days a week and 10 mg daily in prevention of duodenal ulcer relapse. Double-blind comparative trial

In a double-blind, parallel-group clinical trial of 195 patients with duodenal ulcers who after a short-term study had relief of pain and healed ulcers proved endoscopically, 65 were randomized to receive 20 mg omeprazole 3 days a week (once in the morning from Friday to Sunday), 64 to receive 10 mg omeprazole once daily in the morning, and 66 to receive placebo for up to 6 months. The patients underwent repeat endoscopy with biopsy of the gastric fundic mucosa (qualitative assessment of argyrophilic cell population), assessment of symptoms, and laboratory screening with measurement of basal serum gastrin concentrations at 3 and 6 months or more often if indicated by recurrence of symptoms. At 3 months, endoscopically proved ulcer relapse occurred in 16% receiving 20 mg omeprazole 3 days a week; 21% receiving 10 mg omeprazole daily; and 50% receiving placebo. At 6 months, corresponding rates were 23%, 27%, and 67% with 95% confidence intervals of difference between the placebo group and omeprazole groups of 28%-60% and 24%-56% (P less than 0.00001), respectively, and between omeprazole groups of -19%-11% (NS). No major clinical or laboratory side effects were noted. Thus both omeprazole regimens are effective and safe in preventing duodenal ulcer relapse.

Abolition by omeprazole of aspirin induced gastric mucosal injury in man

This study investigates whether aspirin injury to the human gastric mucosa can be prevented by profound acid suppression with omeprazole, in a randomised, double blind, crossover design according to latin square. It was concluded that profound acid suppression can prevent aspirin induced gastric mucosal injury in normal subjects. This approach may prevent the development of peptic ulcers and their complications in patients taking aspirin and other non-steroidal anti-inflammatory drugs.

Effect of 10 mg and 20 mg omeprazole daily on duodenal ulcer: double-blind comparative trial

One-hundred and seventy-one patients with endoscopically proven duodenal ulcers were allocated at random to double-blind treatment with 10 or 20 mg of omeprazole in the morning for up to 4 weeks. Patients completed the study if ulcer healing and pain relief had occurred at 2 weeks. A total of 155 patients completed the trial. Patients treated with 20 mg of omeprazole daily responded significantly more rapidly than those treated with 10 mg of omeprazole daily (P less than 0.001; Cochran-Mantel-Haenszel test covering both time points), cumulative healing rates at 2 and 4 weeks were 74% (58/78) and 91% (71/78), respectively. The corresponding rates in the group treated with 10 mg daily were 48% (39/81) and 75% (58/77). Pain relief was again more pronounced during treatment with the larger dose (P less than 0.05; stratified Wilcoxon test). No major clinical or biochemical side effects were noted. An omeprazole dose of 20 mg daily is preferable to a lower dose for the treatment of duodenal ulcer disease in the short term.

Healing and relapse of severe peptic esophagitis after treatment with omeprazole

We have studied the response of erosive or ulcerative esophagitis to treatment with omeprazole and its subsequent relapse on cessation of therapy in 196 patients. In the first phase of the study omeprazole (20 or 40 mg daily) was compared with placebo in 64 patients. After 4 wk there was endoscopic healing in 81% (25 of 31) of omeprazole-treated patients and in only 6% (2 of 32) of placebo-treated patients. Endoscopic healing of esophagitis was accompanied by symptom relief and histologic healing of ulceration. In the second (dose finding) phase a further 132 patients were randomized to omeprazole (20 or 40 mg daily) and endoscopic healing was assessed. In patients with the mildest grade of ulcerative esophagitis (grade 2), healing occurred at 4 wk in 87% receiving 20 mg and in 97% receiving 40 mg. In patients with grade 3 esophagitis, 67% (20 mg) and 88% (40 mg) were healed. Less than half the patients with grade 4 esophagitis (Barrett's ulcers or confluent ulceration) healed with either 20 mg (48%) or 40 mg (44%). Regression analysis in the 164 omeprazole-treated patients showed no evidence that healing was influenced by factors other than severity of esophagitis at entry and omeprazole dose. In phase 3 of the study the rate of endoscopic relapse was determined in 107 endoscopically healed patients after stopping omeprazole. Erosive or ulcerative esophagitis recurred in 88 of 107 (82%) by 6 mo. Neither initial dose, grade of esophagitis, nor smoking was shown to influence relapse rate. Omeprazole is a highly effective treatment for peptic esophagitis. The 40-mg/day dosage produces endoscopic healing slightly more quickly than the 20-mg/day dosage, and the initial endoscopic gradings are of prognostic value. Relapse occurs rapidly when treatment is stopped.

Omeprazole. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in peptic ulcer disease and Zollinger-Ellison syndrome

Omeprazole is a substituted benzimidazole derivative which markedly inhibits basal and stimulated gastric acid secretion. It has a unique mode of action, irreversibly blocking the so-called proton pump of the parietal cell which is supposedly the terminal step in the acid secretory pathway. In animals, on a weight basis, omeprazole is 2 to 10 times more potent than cimetidine in inhibiting gastric acid secretion. Toxicological studies in rats have shown that very high doses of omeprazole administered for 2 years produce hyperplasia of gastric enterochromaffin-like cells and carcinoids, a few with proliferations into the submucosa. The significance of such findings to the clinical situation is wholly speculative and requires further research. Preliminary studies in patients with duodenal ulcers or Zollinger-Ellison syndrome have found no mucosal changes which would suggest that the drug represents a risk for development of carcinoid tumours at therapeutic dosages. In patients with duodenal ulcers omeprazole, at dosages of at least 20mg once daily, produced ulcer healing rates of between 60 and 100% after 2 weeks and between 90 and 100% after 4 weeks, even in patients resistant to treatment with H2-receptor antagonists. Comparative trials clearly demonstrated that omeprazole 20 to 40 mg administered once daily was significantly more effective than usual dosage regimens of cimetidine and ranitidine in healing duodenal ulcers during 2 to 4 weeks of treatment. At present no data are available evaluating omeprazole as maintenance therapy once ulcers have healed. Other clinical trials have also shown that omeprazole is effective for treating gastric ulcers, ulcerative peptic oesophagitis, and Zollinger-Ellison syndrome. In patients with Zollinger-Ellison syndrome the profound and long lasting antisecretory activity of omeprazole may make it the drug of choice for treating the massive acid hypersecretion associated with the disease, especially when H2-receptor antagonists are ineffective. During clinical trials reported to date omeprazole has been very well tolerated but further clinical experience is essential to fully evaluate its safety profile. Thus, omeprazole represents a pharmacologically unique antisecretory drug which is very effective for rapidly healing peptic ulcers and peptic oesophagitis, and for reducing gastric acid hypersecretion in patients with Zollinger-Ellison syndrome. If the apparent absence of undesirable mucosal morphological changes during treatment with usual doses in patients with peptic ulcer disease is confirmed, it may be a major advance in the treatment of these diseases.

Long term management of hemorrhagic esophagitis with cimetidine and omeprazole

We report a patient whose severe recurrent anemia was due to overt and occult hemorrhage from peptic esophagitis. Cimetidine treatment was successful for seven years but dose reduction was followed by intractable hemorrhage which did not respond to H2-receptor antagonists. Omeprazole therapy produced dramatic remission of symptoms and anemia.