Intravenous pantoprazole rapidly controls gastric acid hypersecretion in patients with Zollinger-Ellison syndrome

BACKGROUND & AIMS: Parenteral control of gastric acid hypersecretion in conditions such as Zollinger-Ellison syndrome (ZES) or idiopathic gastric acid hypersecretion is necessary perioperatively or when oral medications cannot be taken for other reasons (e.g., during chemotherapy, acute upper gastrointestinal bleeding, or in intensive care unit settings). METHODS: We evaluated the efficacy and safety of 15-minute infusions of the proton pump inhibitor pantoprazole (80-120 mg every 8-12 hours) in controlling acid output for up to 7 days. Effective control was defined as acid output >10 milliequivalents per hour (mEq/h) (<5 mEq/h in patients with prior acid-reducing surgery) for 24 hours. RESULTS: The 21 patients enrolled had a mean age of 51.9 years (range, 29-75) and a mean disease duration of 8.1 years (range, <0.5-21); 13 were male, 7 had multiple endocrine neoplasia syndrome type I, 4 had undergone acid-reducing surgery, 2 had received chemotherapy, and 13 had undergone gastrinoma resections without cure. Basal acid output (mean +/- SD) was 40.2 +/- 27.9 mEq/h (range, 11.2-117.9). In all patients, acid output was controlled within the first hour (mean onset of effective control, 41 minutes) after an initial 80-mg intravenous pantoprazole dose. Pantoprazole, 80 mg every 12 hours, was effective in 17 of 21 patients (81%) for up to 7 days. Four patients required upward dose titration, 2 required 120 mg pantoprazole every 12 hours, and 2 required 80 mg every 8 hours. At study end, acid output remained controlled for 6 hours beyond the next expected dose in 71% of patients (n = 15); mean acid output increased to 4.0 mEq/h (range, 0-9.7). No serious or unexpected adverse events were observed. CONCLUSIONS: Intravenous pantoprazole, 160-240 mg/day administered in divided doses by 15-minute infusion, rapidly and effectively controlled acid output within 1 hour and maintained control for up to 7 days in all ZES patients.     

Low-dose intravenous pantoprazole for optimal inhibition of gastric acid in Korean patients

BACKGROUND AND AIM: Proton-pump inhibitor (PPI) therapy for bleeding ulcers is more efficacious in Asian patients than in non-Asian patients. The aim of this study was to evaluate the efficacy of various doses of pantoprazole on intragastric acidity in Korean patients. METHODS: A prospective randomized study was conducted in 52 patients either with bleeding peptic ulcers after successful endotherapy or who received endoscopic mucosal resection for gastric neoplasms. Patients were randomized into two doses of intravenous pantoprazole: 40 mg q.d. and 40 mg b.i.d. We compared these results with our preliminary study utilizing high-dose pantoprazole (80 mg + 8 mg/h). The potential contribution of CYP2C19 genetic polymorphisms and the presence of Helicobacter pylori were also assessed. RESULTS: Pantoprazole 40 mg b.i.d. and high-dose pantoprazole demonstrated better inhibition of intragastric acid than pantoprazole q.d. (P < 0.05). The pantoprazole 40 mg q.d. group exhibited significant variations in acid inhibition correlating with CYP2C19 genotype. Median 24 h pH values did not differ significantly between the pantoprazole b.i.d. and high-dose pantoprazole groups, regardless of H. pylori infection status. A median intragastric pH < 6.0 was observed in only three of 28 patients in the 40 mg b.i.d. group; these three patients were extensive metabolizers. CONCLUSION: A 40 mg b.i.d. dose of pantoprazole is sufficient to maintain pH > 6.0 in Korean patients, except for patients with extensive metabolizing CYP2C19 genotypes.     

Intravenous Pantoprazole as Initial Treatment in Patients With Gastroesophageal Reflux Disease and a History of Erosive Esophagitis: A Randomized Clinical Trial

We sought to evaluate safety and efficacy of IV pantoprazole when used as initial therapy in patients with gastroesophageal reflux disease (GERD) and a history of erosive esophagitis (EE) in a double-blind, placebo-controlled, randomized, parallel-group study. Patients were randomized to 7 days of once-daily IV or oral pantoprazole (40 mg) or placebo. Efficacy variables included maximal acid output, basal acid output, and changes from baseline in frequency/severity of GERD symptoms, and frequency of antacid usage. Seventy-eight patients were randomized (n=26/27/25 [IV/oral/placebo]). Mean maximal acid output was 8.4, 6.3, and 20.9 mEq/h for IV or oral pantoprazole, and placebo, respectively. For pantoprazole versus placebo, maximal and basal acid output were significantly lower (P<.001) and there was a numerical trend toward improved GERD and antacid usage. Both treatments were well tolerated. In conclusion, IV/oral pantoprazole were similarly effective in suppressing basal and pentagastrin-stimulated gastric acid secretion in GERD patients with a history of EE.     

Inhibition of Pentagastrin-Stimulated Gastric Acid Secretion by Pantoprazole and Omeprazole in Healthy Adults

Our objective was to compare the onset and duration of a single dose of pantoprazole or omeprazole on maximally stimulated gastric acid secretion. This double-blind, randomized, placebo-controlled study involved 36 healthy adults and utilized continuous pentagastrin infusion to stimulate acid secretion after administration of pantoprazole, 40 mg, omeprazole, 20 mg, or placebo. Gastric aspirates were collected over 24 hr and analyzed for volume, pH, and hydrogen ion concentration, and gastric acid outputs (GAO) were calculated. Comparison between GAO and intragastric pH was performed. Pantoprazole resulted in significantly greater inhibition of GAO than omeprazole. Mean cumulative 24-hr GAO was 164 ± 130 mEq for pantoprazole versus 283 ± 159 mEq for omeprazole (P = 0.031). Pantoprazole patients reached and maintained GAO levels below the 10-mEq/hr threshold at 5.7 hr, whereas omeprazole patients never reached this threshold. We conclude that pantoprazole significantly suppressed gastric acid secretion compared to omeprazole. Comparisons between pH and GAO showed that GAO was a more appropriate measure of gastric acid secretion than intragastric pH. This work received financial support from Wyeth Pharmaceuticals.     

Rebamipide, a Cytoprotective Drug, Increases Gastric Mucus Secretion in Human: Evaluations with Endoscopic Gastrin Test

We have previously developed a rapid, simple endoscopic method for evaluating gastrin-stimulated maximal acid output (the endoscopic gastrin test, EGT). In EGT, gastric fluid newly secreted over 10 min after gastrin stimulation is collected under direct endoscopic visualization. In this study, employing the EGT, we evaluated the effect of rebamipide, a cytoprotective anti-ulcer drug, on gastric mucus secretion. In ten Helicobacter pylori-negative healthy volunteers, gastric juice was collected by EGT prior to and after 4-week administration of rebamipide. The collected gastric juice was subjected to analysis for gastric mucus output. Total gastric mucin output was significantly increased by 53% by rebamipide administration from 3.2 ± 1.2 mg hexose/10 min to 4.9 ± 2.2 mg hexose/10 min (P < 0.01). Further analysis by ion-exchange chromatography revealed that rebamipide administration induced a specific increase in acidic mucin rich in sialic acid. Applying EGT, this study demonstrated that rebamipide administration increased gastric mucus secretion in human.     

Oral and intravenous dosage forms of pantoprazole are equivalent in their ability to suppress gastric acid secretion in patients with gastroesophageal reflux disease

OBJECTIVE: The aim of this study was to assess the ability of pantoprazole to maintain gastric acid suppression in patients with gastroesophageal reflux disease who are switched from an oral (p.o.) to an intravenous (i.v.) dosage form. METHODS: A total of 65 patients with gastroesophageal reflux disease were administered either 40 or 20 mg of p.o. pantoprazole daily for 10 days, then were switched to either a matching dose of i.v. pantoprazole or to placebo for 7 days. Acid output (basal and maximal) was measured at the end of the p.o. treatment period and on the first and last days of i.v. therapy. In the primary efficacy analysis, the acid output values at the end of the p.o. pantoprazole treatment were compared with those at the end of the i.v. treatment. Safety was monitored by periodic vital sign measurements, clinical laboratory evaluations, ophthalmic examinations, electrocardiograms, and reports of adverse events. The data were tested by an analysis of covariance and by Wilcoxon signed rank and t tests. RESULTS: Maximal acid output (mean +/- SD) in the 40 mg and 20 mg pantoprazole group after p.o. treatment was 6.5 +/- 5.6 mEq/h and 14.5 +/- 15.5 mEq/h, respectively; whereas, at the end of the i.v. treatment period, the values were 6.6 +/- 6.3 mEq/h and 11.1 +/- 10.2 mEq/h, respectively. In patients given i.v. placebo, acid output was significantly (p < 0.05) increased to 29.2 +/- 13.0 mEq/h by day 7. Both p.o. and i.v. pantoprazole dosage forms had similar favorable safety and tolerability profiles. CONCLUSIONS: The p.o. and i.v. formulations of pantoprazole (40 and 20 mg) are equivalent in their ability to suppress gastric acid output. The i.v. form of pantoprazole offers an alternative for gastroesophageal reflux disease patients who are unable to take the p.o. formulation.     

Efecto sobre el pH intragástrico de 20 mg de levopantoprazol versus 40 mg de pantoprazol racémico durante los primeros 7 días de tratamiento en pacientes con enfermedad por reflujo gastroesofágico

Introduction/aimLevo-pantoprazole, the S-enantiomer of pantoprazole, is a proton pump inhibitor that has been shown in animal studies to be faster and stronger than its racemic formulation. There are no studies on humans and therefore our aim was to evaluate the effects of levo-pantoprazole versus racemic pantoprazole on intragastric pH.Materials and methodsA randomized controlled study was conducted on patients with erosive gastroesophageal reflux disease that were given 20 mg of levo-pantoprazole (n = 15) versus 40 mg of racemic pantoprazole (n = 15) for 7 days. Baseline and end-of-treatment symptom evaluation and intragastric pH measurement were carried out.ResultsThere were no differences between the groups in the baseline evaluations. From 40 to 115 min after the first dose of levo-pantoprazole, the mean intragastric pH was higher, compared with that of racemic pantoprazole (p < 0.05). After one week, levo-pantoprazole and racemic pantoprazole significantly reduced intragastric acid production and its esophageal exposure (p < 0.05). Even though there was no statistically significant difference, a larger number of patients that received levo-pantoprazole stated that their heartburn improved within the first 3 days.ConclusionsThe S-enantiomer of pantoprazole (levo-pantoprazole) had a faster and stronger effect with respect to acid suppression, compared with its racemic formulation. Although the effect on symptoms was faster with levo-pantoprazole, occurring within the first days of treatment, it was equivalent to that of the racemate at one week of treatment.     

Inhibition of pentagastrin-induced gastric acid secretion by intravenous pantoprazole: a dose-response study

OBJECTIVE: The purpose of this study was to compare the gastric acid inhibitory ability of increasing doses of intravenous (i.i.) pantoprazole with that of i.v. famotidine and placebo. Pentagastrin was infused continuously in healthy subjects as a model for patients with Zollinger-Ellison syndrome. METHODS: Pentagastrin (1 microg/kg/h) was infused to stimulate maximum acid output in 39 subjects over a 25-h period. After 60 min of pentagastrin infusion, subjects received a single dose of i.v. pantoprazole (20, 40, 80, or 120 mg), i.v. famotidine (20 mg), or saline placebo. The variables measured were onset of response (time until acid output fell to < 10 mEq/h), duration of response (time acid output remained < 10 mEq/h), and cumulative acid output over 24 h. RESULTS: All doses of i.v. pantoprazole produced a dose-dependent suppression of acid output to < 10 mEq/h. Single i.v. doses of pantoprazole, 80 and 120 mg, suppressed acid output by > 90% in all subjects for < or = 21 h and had an onset of action of < 1 h. CONCLUSIONS: Intravenous pantoprazole has a rapid onset and a clear dose-related effect, with a significantly longer duration of action than that of i.v. famotidine.     

Comparison of omeprazole and ranitidine in treatment of refractory gastroesophageal reflux disease in patients with gastric acid hypersecretion

Secretion of gastric acid and volume, serum gastrin concentration, and ambulatory 24-hr esophageal pH monitoring were evaluated prospectively in 12 patients with idiopathic gastric acid hypersecretion (basal acid output greater than 10.0 meq/hr) undergoing treatment for refractory chronic long-standing pyrosis. Treatment lasted six months and consisted of three months of ranitidine (mean 2150 mg/day, range 1200–3000 mg/day), followed by three months of omeprazole (mean 33 mg/day, range 20–60 mg/day). Both ranitidine and omeprazole significantly reduced gastric acid output (P<0.001) and gastric volume output (P<0.001) compared to a basal evaluation and resulted in complete disappearance of pyrosis. Total reflux time (percent 24 hr intraesophageal pH less than 4) was significantly reduced by ranitidine (P<0.02) and omeprazole (P<0.001) compared to basal evaluation; however, the effects of omeprazole were significantly greater than ranitidine (P<0.05). Omeprazole caused a significant increase in serum gastrin concentration compared to both basal and ranitidine (P<0.05). Endoscopically documented erosive esophagitis was present in nine of the 12 patients, and seven of the 12 patients had Barrett's epithelium. All 12 patients had complete resolution of pyrosis and healed esophagitis by six months, but no significant endoscopic regression was observed in the extent of Barrett's epithelium. No side effects occurred with these high doses of ranitidine or omeprazole. These results indicate that high-dose ranitidine and omeprazole are effective therapy for refractory gastroesophageal reflux disease. However, with omeprazole, total reflux times are reduced more than with ranitidine, often into the normal range. That marked reduction of gastric acid secretion with omeprazole, which greatly reduces total reflux times, accounts for the significant elevation of serum gastrin concentration seen during omeprazole therapy.     

Bolus or intravenous infusion of ranitidine: effects on gastric pH and acid secretion. A comparison of relative efficacy and cost

STUDY OBJECTIVE: To compare the effects of intravenous bolus injection of ranitidine, continuous intravenous infusion of ranitidine, and placebo on gastric pH, acid secretion, and plasma ranitidine concentration during a 24-hour period, and to determine by survey the use, delivery methods, and costs of histamine H2-receptor antagonists in intensive care units. DESIGN: Double-blind, Latin-square randomized, prospective measurement of the gastric pH, acid output, and plasma ranitidine concentration over 24 hours in response to six treatment regimens in 12 patients with inactive duodenal ulcer. Eight regional hospitals were surveyed to obtain information on the use of histamine H2-receptor antagonists. INTERVENTIONS: Gastric acid secretion, pH, and plasma ranitidine were monitored for 24 hours on six separate days in response to placebo, intravenous bolus injection of ranitidine (50 mg every 8 hours and 75 mg every 12 hours), and continuous intravenous infusion of ranitidine (75, 150, and 300 mg every 24 hours). MEASUREMENTS AND MAIN RESULTS: Intravenous infusions were significantly more effective than bolus injections. After bolus injections, hourly gastric pH values fluctuated widely, from 7.6 to 1.6, whereas during continuous infusion of 150 mg and 300 mg, hourly pH values were 3.8 or greater. The gastric pH was greater than 4.0 in 75% +/- 5% and 83% +/- 6% of determinations done during continuous intravenous infusion of 150 mg and 300 mg, respectively. Fluctuations in the plasma ranitidine concentration corresponded with changes in gastric pH and acid secretion. Histamine H2-receptor antagonists were prescribed for about 75% of patients in intensive care units and were most commonly administered by bolus rather than infusion (5:1); the cost was approximately +40 per day less by infusion. CONCLUSIONS: On the basis of both efficacy and cost, intermittent bolus injections should be discontinued and replaced by continuous intravenous infusion in hospitalized patients requiring treatment with histamine H2-receptor antagonists. If ranitidine is used, either 150 mg or 300 mg administered as a 24-hour continuous infusion is most effective.     

Pantoprazole versus omeprazole: influence on meal-stimulated gastric acid secretion

AIMS: To determine the influence of recommended therapeutic doses of pantoprazole and omeprazole on meal-stimulated acid secretion. METHODS: In this double-blind, placebo-controlled, three-period crossover study, 12 healthy male volunteers received 40 mg pantoprazole od, 20 mg omeprazole od or placebo at 08:00 h for 5 days in a randomized order. Meal-stimulated acid secretion was determined by means of a homogenized test meal, and intragastric titration on day 1, 4-6 h, 8-10 h, 16-18 h, and 24-26 h, and on days 3 and 5, 4-6 h after oral drug administration. RESULTS: On day 1 (4-6 h after oral drug administration), meal-stimulated acid secretion was decreased by 36% and 24% after administration of 40 mg pantoprazole or 20 mg omeprazole, respectively. After 3 and 5 days of dosing, the decreases were 88% and 85% with 40 mg pantoprazole, and 70% and 74% with 20 mg omeprazole. At all measuring points during the 5-day dosing periods, 40 mg pantoprazole proved superior to 20 mg omeprazole in inhibiting meal-stimulated gastric acid secretion. The differences were statistically significant for pantoprazole on day 1, 24-26 h after oral drug administration and on day 3 (P = 0.0425 and P = 0.0244, respectively). On day 1, only pantoprazole was significantly better than placebo (P = 0.0210, 4-6 h after dosing; P = 0.0093, 8-10 h after dosing and P = 0.0068, 16-18 h after dosing). CONCLUSION: Pantoprazole 40 mg is significantly more effective than omeprazole 20 mg in inhibiting meal-stimulated acid secretion. In addition, pantoprazole exhibits a more rapid onset of action.     

Protecting against the acid aspiration syndrome in adult patients undergoing emergency surgery.

This paper has studied the effect of i.v. cimetidine and ranitidine, given 1 h prior to anesthesia, on gastric volume and pH in three homogeneous groups undergoing emergency surgery. Group I (10 patients) received placebo, group II (20 patients) cimetidine 400 mg in saline solution, and group III (20 patients) ranitidine 150 mg in saline. Standardised premedication was administered and anesthesia induced. Immediately after tracheal intubation the stomach contents were aspirated and analysed for volume and pH. There were no significant differences in gastric volume among the three groups. However, treated patients had significantly elevated pH as compared with the control group and the number of patients at risk (pH < 2.5 and volume > 25 ml) was significantly smaller at 20% and 15%, respectively, than in the control group (40%). It is concluded that cimetidine 400 mg, and ranitidine 150 mg i. v., given about 70 min. prior to induction of anesthesia may decrease the risk of the acid aspiration syndrome in emergency operations.     

Intravenous ibandronate injections in postmenopausal women with osteoporosis: One‐year results from the dosing intravenous administration study

Objective

Although oral bisphosphonates are effective treatments for postmenopausal women with osteoporosis, oral dosing may be unsuitable for some patients. An efficacious intravenously administered bisphosphonate could be beneficial for such patients. Ibandronate, a potent nitrogen‐containing bisphosphonate, can be administered using extended dosing intervals, either orally or by rapid intravenous injection. The aim of this study was to identify the optimal intravenous dosing regimen for ibandronate in postmenopausal women with osteoporosis.

Methods

In a randomized, double‐blind, double‐dummy, phase III, noninferiority study, we compared 2 regimens of intermittent intravenous injections of ibandronate (2 mg every 2 months and 3 mg every 3 months) with a regimen of 2.5 mg of oral ibandronate daily, the latter of which has proven antifracture efficacy. The study group comprised 1,395 women (ages 55–80 years) who were at least 5 years postmenopausal. All patients had osteoporosis (lumbar spine [L2−L4] bone mineral density [BMD] T score less than −2.5). Participants also received daily calcium (500 mg) and vitamin D (400 IU). The primary end point was change from baseline in lumbar spine BMD at 1 year. Changes in hip BMD and in the level of serum C‐telopeptide of type I collagen (CTX) were also measured, as were safety and tolerability.

Results

At 1 year, mean lumbar spine BMD increases were as follows: 5.1% among 353 patients receiving 2 mg of ibandronate every 2 months, 4.8% among 365 patients receiving 3 mg of ibandronate every 3 months, and 3.8% among 377 patients receiving 2.5 mg of oral ibandronate daily. Both of the intravenous regimens not only were noninferior, but also were superior (P < 0.001) to the oral regimen. Hip BMD increases (at all sites) were also greater in the groups receiving medication intravenously than in the group receiving ibandronate orally. Robust decreases in the serum CTX level were observed in all arms of the study. Both of the intravenous regimens were well tolerated and did not compromise renal function.

Conclusion

As assessed by BMD, intravenous injections of ibandronate (2 mg every 2 months or 3 mg every 3 months) are at least as effective as the regimen of 2.5 mg orally daily, which has proven antifracture efficacy, and are well tolerated.

     

Impact of long-term ranitidine and pantoprazole on accuracy of [13C]urea breath test

No previous study has analyzed the impact of long-term antisecretory drugs on the precision of [¹³C]urea breath test (UBT). We assessed the rate of UBT conversion from positive to negative results during 60-day therapy with standard doses of ranitidine and pantoprazole. For this purpose, we recruited 60 dyspeptic patients with H. pylori infection ascertained on the basis of the concomitant results of CLO-test, histology, and UBT. Our patients were randomly assigned to receive ranitidine 300 mg at night or pantoprazole 40 mg in the morning for 60 days. UBT was performed at baseline and on days 14, 30, and 60, while patients were still taking antisecretory drugs. Patients with false-negative UBT on day 60 repeated the test every 3 days until conversion. After overnight fasting, duplicate breath test samples were taken from each patient before and 30 min after ingestion of 75 mg [¹³C]urea dissolved in 150 ml of 0.033 mol/liter citric acid. Four patients dropped out of the study. Both drugs induced similar false-negative UBTs on day 14 of dosing (P = 0.5). Afterwards, the three false-negative UBTs in the ranitidine group again became positive during therapy and particularly on day 30 of dosing. Of the four false-negative UBTs in the pantoprazole group at day 60, one became positive after 3 and three after 9 days of therapy cessation. Our findings show that the long-term use of ranitidine and pantoprazole at standard doses has different effects on the results of UBT. In the pantoprazole group patients again became positive within 3–9 days after stopping 60-day therapy, whereas in the ranitidine group patients reverted to positive on day 30 of dosing while they were still on treatment and this was likely due to development of tolerance. Therefore, patients taking pantoprazole need at least a 10-day withdrawal before UBT testing, while those taking ranitidine for at least 30 days can undergo UBT without the necessity of a wash-out period.     

Replacement of oral proton pump inhibitors with intravenous pantoprazole to effectively control gastric acid hypersecretion in patients with Zollinger-Ellison syndrome

OBJECTIVES: In patients with Zollinger-Ellison syndrome (ZES) or other conditions requiring oral doses of proton pump inhibitors, it frequently becomes necessary to use parenterally administered gastric acid inhibitors. However, i.v. histamine-2 receptor antagonists are not effective at usual doses and lose their effectiveness because of tachyphlaxis. With the approval in the United States of i.v. pantoprazole, a substituted benzimidazole available in i.v. formulation, it will become possible to acutely manage gastric acid secretion in the acute care setting of a hospital. This study was developed to monitor the safety and establish the efficacy of i.v. pantoprazole as an alternative to oral proton pump inhibitors for the control of gastric acid hypersecretion in patients with ZES. METHODS: The efficacy of replacing oral PPI therapy with i.v. pantoprazole was evaluated in 14 ZES patients. After study enrollment, patients taking their current doses of oral PPI (omeprazole or lansoprazole) were switched to pantoprazole i.v. for 6 days during an 8-day inpatient period in the clinical research center. Effective control was defined as an acid output (AO) of < 10 mEq/h (< 5 mEq/h in patients with prior gastric acid-reducing surgery). RESULTS: The mean age of the 14 patients enrolled in the study was 52.4 yr (range = 38-67). Mean basal AO was 0.55 +/- 0.32 mEq/h and mean fasting gastrin was 1089 pg/ml (range = 36-3720). Four patients were also diagnosed with the multiple endocrine neoplasia type I syndrome, nine were male, and two had previously undergone acid-reducing surgery. Before study enrollment, gastric acid hypersecretion was controlled in nine of 14 patients with omeprazole (20-200 mg daily) and five of 14 with lansoprazole (30-210 mg daily). In the oral phase of the study all patients had adequate control of gastric acid secretion, with a mean AO of 0.55 +/- 0.32 mEq/h (mean +/- SEM). Thereafter, 80 mg of i.v. pantoprazole was administered b.i.d. for 7 days by a brief (15 min) infusion and the dose was titrated upward to a predetermined maximum of 240 mg/24 h to control AO. A dose of 80 mg b.i.d. of i.v. pantoprazole controlled AO in 13 of 14 of the patients (93%) for the duration of the study (p > 0.05 compared to baseline values for all timepoints). One sporadic ZES patient (oral control value = 0.65 mEq/h on 100 mg of omeprazole b.i.d. p.o.) was not controlled with 80 mg of i.v. pantoprazole b.i.d. and dosage was titrated upward to 120 mg b.i.d. after day 2. CONCLUSIONS: There were no serious adverse events observed. Intravenous pantoprazole provides gastric acid secretory control that is equivalent to the acid suppression observed with oral proton pump inhibitors. Most ZES patients (93%) maintained effective control of AO previously established with oral PPIs when switched to 80 mg of i.v. pantoprazole b.i.d.; however, for difficult-to-control patients, doses > 80 mg b.i.d. may be required.     

A Glass of Water Immediately Increases Gastric pH in Healthy Subjects

Onset of action of antisecretory agents is of pivotal importance for patients with gastroesophageal reflux disease (GERD) treated “on-demand.” Aim To study the acute effect of acid-inhibiting drugs and water administration on gastric pH. Method A cross-over study was performed in 12 H. pylori (-), healthy subjects (6 men; mean age: 26 years). A single oral dose of the following agents was received with a wash-out period between each study: a glass of water (200 ml), antacid, ranitidine, omeprazole, esomeprazole, and rabeprazole. Gastric pH was recorded for 6 h after drug intake. Results Water increased gastric pH >4 in 10/12 subjects after 1 min. The time (median) needed to pH >4 was for: antacid 2 min, ranitidine 50 min, omeprazole 171 min, esomeprazole 151 min, and rabeprazole 175 min. Gastric pH >4 lasted for 3 min after water and for 12 min after antacids; it remained >4 until the end of recording in: 4/12 subjects with ranitidine, 11/12 with rabeprazole, and all with omeprazole and esomeprazole. Conclusion Water and antacid immediately increased gastric pH, while PPIs showed a delayed but prolonged effect compared to ranitidine.     

Gastric acid control with esomeprazole, lansoprazole, omeprazole, pantoprazole, and rabeprazole: a five-way crossover study

OBJECTIVES: Proton pump inhibitors owe their clinical efficacy to their ability to suppress gastric acid production. The objective of this study was to evaluate and compare intragastric pH following standard doses of esomeprazole, lansoprazole, omeprazole, pantoprazole and rabeprazole. METHODS: This randomized, open-label, comparative five-way crossover study evaluated the 24-h intragastric pH profile of oral esomeprazole 40 mg, lansoprazole 30 mg, omeprazole 20 mg, pantoprazole 40 mg, and rabeprazole 20 mg once daily in 34 Helicobacter pylori-negative patients aged 18-60 yr with symptoms of gastroesophageal reflux disease. Patients were randomly assigned to one of five treatment sequences and study drug was taken on 5 consecutive mornings 30 minutes prior to a standardized breakfast. A washout period of at least 10 days separated each treatment phase. RESULTS: Thirty-four patients provided evaluable data for all five comparators. The mean number of hours of evaluable pH data was > or =23.75 hours. On day 5, intragastric pH was maintained above 4.0 for a mean of 14.0 h with esomeprazole, 12.1 h with rabeprazole, 11.8 h with omeprazole, 11.5 h with lansoprazole, and 10.1 h with pantoprazole (p < or = 0.001 for differences between esomeprazole and all other comparators). Esomeprazole also provided a significantly higher percentage of patients with an intragastric pH greater than 4.0 for more than 12 h relative to the other proton pump inhibitors (p < 0.05). The frequency of adverse events was similar between treatment groups. CONCLUSIONS: Esomeprazole at the standard dose of 40 mg once daily provided more effective control of gastric acid at steady state than standard doses of lansoprazole, omeprazole, pantoprazole, and rabeprazole in patients with symptoms of gastroesophageal reflux disease.     

Oral pantoprazole for acid suppression in the treatment of patients with Zollinger-Ellison syndrome.

BACKGROUND: The management of patients with gastric acid hypersecretion due to gastrinoma, usually recognized as Zollinger-Ellison syndrome (ZES), was radically changed 10 years ago by the use of proton pump inhibitors. Surgical treatment now concentrates on tumour excision, and in the majority of patients, gastrectomy is no longer required to prevent complications of acid hypersecretion that can be managed pharmacologically. AIMS: To verify the ability of pantoprazole to control gastric acid hypersecretion and the clinical effects of acid hypersecretion in seven patients with documented ZES. METHODS: Pantoprazole was administered at an initial dose of 80 mg daily for seven days before basal acid output (BAO) was measured at 08:00, ie, 1 h before the next dose of pantoprazole was normally ingested. A lower (40 mg) or higher (120 mg or more) dose of pantoprazole was then used to keep the BAO in the therapeutic range (between 0.1 and 10 mmol/h) and to control clinical symptoms such as acid-related pain or diarrhea. RESULTS: BAO and clinical symptoms were controlled with pantoprazole 40 mg daily in one patient, 80 mg daily in two patients, 120 mg daily in three patients and 160 mg daily in one patient. CONCLUSIONS: Pantoprazole was able to control acid hypersecretion in ZES patients when administered in doses between 40 and 160 mg daily. An initial dose of 120 mg given before further titration of the drug regimen appears to be a reasonable therapeutic strategy.     

Nasogastric Omeprazole: Effects on Gastric pH in Critically Ill Patients

Objective: The efficacy of omeprazole administered by the nasogastric route has not been adequately studied. We sought to determine whether nasogastrically administered omeprazole could effectively maintain an intra-gastric pH greater than 4.0 in patients hospitalized in a medical intensive care unit. Methods: Patients were considered eligible for the study if they had a nasogastric feeding tube in place and had not received omeprazole, antacids, or histamine-2 blockers in the 5 days preceding study enrollment. Exclusionary criteria included active GI bleeding or a mean baseline gastric pH greater than 4.0. Patients served as their own controls during a 24-h lead-in period, during which baseline intragastric pH was measured by gastric aspirate. Omeprazole, 20 or 40 mg, was administered once daily with water through a nasogastric tube. Intragastric pH was measured every 4–8 h for a maximum of 3 days following drug administration. Results: Twenty patients were considered eligible for the study; 10 were excluded because of an elevated baseline gastric pH (n = 8) or because proper gastric aspirates could not be obtained (n = 2). The mean baseline intragastric pH in four patients receiving omeprazole 20 mg q.d. was 2.4 ± 1.1 and increased to 3.7 ± 1.6 after drug administration ( p = 0.013). The mean baseline intragastric pH in six patients receiving omeprazole 40 mg q.d. was 2.8 ± 0.8 and increased to 5.7 ± 1.1 after drug administration ( p < 0.001). The percentage of intragastric pH values greater than 4.0 after drug administration was 34.2% in patients receiving omeprazole 20 mg q.d. and 84.7% in those receiving omeprazole 40 mg q.d. Conclusions: Nasogastric omeprazole 40 mg q.d. is effective in maintaining an intragastric pH greater than 4.0 in critically ill patients. The nasogastric administration of omeprazole offers a costeffective therapeutic option for acid suppression in patients at risk for stress mucosal ulceration.     

Randomized Comparison of Gastric pH Control with Intermittent and Continuous Intravenous Infusion of Famotidine in ICU Patients

Objective : To compare gastric pH control using intravenous famotidine as a primed, continuous infusion versus intermittent infusion. Methods : In a prospective, double-blind study, 40 ICU patients at risk for stress ulceration were randomly assigned to receive either famotidine 20 mg intravenous bolus followed by 1.67 mg/h infusion or famotidine 20 mg intravenously every 12 h. Intraluminal gastric pH was recorded at baseline and every 4 h using a glass electrode. Clinical outcome indicators were also monitored. Subjects were studied for a minimum of 24 h and a maximum of 6 days. Continuous variables were analyzed by ANOVA and nominal variables by Fisher's exact test (α= 0.05). Results : Nineteen patients were randomized to the continuous infusion group, and 21 were randomized to the intermittent group. Using gastric pH greater than 4.0 as an endpoint, the continuous group exhibited better pH control, both in terms of percentage of total measurements (83% versus 63%, p < 0.001) and time spent above pH 4.0 (91% versus 76%, p < 0.01). Similar results were found at pH greater than 5.0 (78% versus 56% for all measurements for the continuous and bolus groups, respectively ( p < 0.001), and 88% versus 72% for the time spent above pH 5.0 ( p < 0.01). Clinical outcomes, including evidence for gastrointestinal bleeding and hospital mortality, did not differ significantly between groups. Conclusion : Famotidine infusion at 1.67 mg/h, when preceded by a bolus dose of 20 mg, provides a greater and more sustained increase in gastric pH than intermittent administration of famotidine 20 mg every 12 h.