Formulation, optimization, and evaluation of raft-forming formulations containing Nizatidine.

OBJECTIVE: The main objective of this research is to formulate, optimize, and evaluate raft-forming chewable tablets of Nizatidine. Various raft-forming agents were used in preliminary screening. Sodium alginate showed maximum raft strength, so tablets were prepared using sodium alginate as the raft forming agent, along with calcium carbonate (CaCO3) as antacid and raft strengthening agent, and sodium bicarbonate (NaHCO3) as a gas generating agent. RESEARCH DESIGN AND METHODS: Raft forming chewable tablets containing Nizatidine were prepared by direct compression and wet granulation methods, and evaluated for drug content, acid neutralization capacity, raft strength, and in-vitro drug release in 0.1 N HCl. Box-Behnken design was used for optimization. RESULTS: Two optimized formulations were predicted from the design space. The first optimized recommended concentrations of the independent variables were predicted to be X1 = 275.92 mg, X2 = 28.60 mg, and X3 = 202.14 mg for direct compression technique and the second optimized recommended concentrations were predicted to be X1 = 253.62 mg, X2 = 24.60 mg, and X3 = 201.77 mg for wet granulation technique. Optimized formulations were stable at accelerated environmental testing for six months at 35 °C and 45 °C with 75% relative humidity. X-Ray showed that the raft floated immediately after ingestion and remained intact for ∼3 h. CONCLUSION: Raft was successfully formed and optimized. Upon chewing tablets, a raft is formed on stomach content. That results in rapid relief of acid burning symptoms and delivering the drug into systemic circulation with enhanced bioavailability.

Glutaraldehyde-crosslinked chitosan-polyethylene oxide nanofibers as a potential gastroretentive delivery system of nizatidine for augmented gastroprotective activity.

Nizatidine (NIZ), a histamine H2-receptor antagonist, is soluble and stable in the stomach, however, it exhibits a short half-life and a rapid clearance. Therefore, chitosan (CS) and polyethylene oxide (PEO) nanofibers (NFs) at different weight ratios were prepared by electrospinning and characterized. The selected uncrosslinked and glutaraldehyde-crosslinked NFs were investigated regarding floating, solid-state characteristics, in vitro release, and in vitro cytotoxicity. The cytoprotective activity against ethanol-induced gastric injury in rats was evaluated through macroscopical, histopathological, immunohistochemical, and oxidative stress examinations. NFs based on 8:2 CS:PEO exhibited the smallest diameter (119.17 ± 22.05 nm) and the greatest mucoadhesion (22.82 ± 3.21 g/cm2), so they were crosslinked with glutaraldehyde. Solid-state characterization indicated polymers interaction, a successful crosslinking, and NIZ dispersion in NFs. Crosslinking maintained swollen mats at pH 1.2 (swelling% = 29.47 ± 3.50% at 24 h), retarded their erosion at pH 6.8 (swelling%= 84.64 ± 4.91% vs. 25.40 ± 0.79% for the uncrosslinked NFs at 24 h), augmented the floating up to 24 h vs. 10 min for the uncrosslinked NFs at pH 1.2 and prolonged the drug release (%drug released ≥ 93% at 24 h vs. 4 and 5 h for the uncrosslinked NFs at pHs 1.2 and 6.8, respectively). The viability of Caco-2 cells ≥ 86.87 ± 6.86% revealed NFs biocompatibility and unreacted glutaraldehyde removal. Crosslinking of 8:2 CS:PEO NFs potentiated the antiulcer activity (38.98 vs. 8.67 for the uncrosslinked NFs) as well as it preserved the gastric wall architecture, COX-2 expression, and oxidative stress markers levels of the normal rats.

Predictors and correlates for weight changes in patients co-treated with olanzapine and weight mitigating agents; a post-hoc analysis.

BACKGROUND: This study focuses on exploring the relationship between changes in appetite or eating behaviors and subsequent weight change for adult patients with schizophrenia or bipolar disorder treated with olanzapine and adjunctive potential weight mitigating pharmacotherapy. The aim is not to compare different weight mitigating agents, but to evaluate patients' characteristics and changes in their eating behaviors during treatment. Identification of patient subgroups with different degrees of susceptibility to the effect of weight mitigating agents during olanzapine treatment may aid clinicians in treatment decisions. METHODS: Data were obtained from 3 randomized, double-blind, placebo-controlled, 16-week clinical trials. Included were 158 patients with schizophrenia or bipolar disorder and a body mass index (BMI) > or = 25 kg/m2 who had received olanzapine treatment in combination with nizatidine (n = 68), sibutramine (n = 42), or amantadine (n = 48). Individual patients were analyzed for categorical weight loss > or= 2 kg and weight gain > or = 1 kg. Variables that were evaluated as potential predictors of weight outcomes included baseline patient characteristics, factors of the Eating Inventory, individual items of the Eating Behavior Assessment, and the Visual Analog Scale. RESULTS: Predictors/correlates of weight loss > or = 2 kg included: high baseline BMI, low baseline interest in food, and a decrease from baseline to endpoint in appetite, hunger, or cravings for carbohydrates. Reduced cognitive restraint, increase in hunger, and increased overeating were associated with a higher probability of weight gain > or = 1 kg. CONCLUSION: The association between weight gain and lack of cognitive restraint in the presence of increased appetite suggests potential benefit of psychoeducational counseling in conjunction with adjunctive pharmacotherapeutic agents in limiting weight gain during antipsychotic drug therapy. TRIAL REGISTRATION: This analysis was not a clinical trial and did not involve any medical intervention.

Nizatidine for the treatment of pediatric gastroesophageal reflux symptoms: an open-label, multiple-dose, randomized, multicenter clinical trial in 210 children.

BACKGROUND: Gastroesophageal reflux disease (GERD), which is reflux that produces damage or troubling symptoms, afflicts approximately 7% of infants and children to the extent that administration of physician-directed pharmacotherapy is warranted. OBJECTIVE: This study was designed in conjunction with the US Food and Drug Administration (FDA) to assess the tolerability and effectiveness of nizatidine, in different doses and formulations, including a newly formulated premade oral solution, for pediatric GERD. METHODS: Children aged 5 days through 18 years were recruited to this 8-week, open-label, multiple-dose, randomized, parallel-group, multicenter study. The original study design specified that patients aged 5 days through 12 years at study start be given a nizatidine capsule dissolved in infant formula or apple juice depending on patient age ("extemporaneous solution"). Children 13 through 18 years old were to be given the "adult dose" of nizatidine capsules 150 mg BID regardless of body weight. All patients aged < 13 years were randomized in blocks of 4 between 2 dose levels (2.5 and 5 mg/kg per dose BID). A protocol amendment during the study added a newly formulated, more pediatric-appropriate, premade oral solution that was developed at the request of the FDA. This premade formulation ("oral solution") was to replace the extemporaneous solution mixed in infant formula or apple juice. Subsequently, an additional 44 children aged < 13 years old were enrolled in the study and randomized to receive the new nizatidine oral solution for 8 weeks at the same 2 dose levels as used for the extemporaneous solution. Outcome data at 4 and 8 weeks included adverse events (AEs) (severity, relation to study drug, and any relationship to study withdrawal) and effectiveness (investigators' assessment of changes in reflux symptoms and overall physical well-being, and parent/child assessment of change in antacid use). Formal statistical analyses were not planned, but post hoc chi-square analyses were performed. RESULTS: Of 214 children enrolled, 210 (98%) intent-to-treat (ITT) patients received > or = 1 dose; of these, 173 (82%) completed 8 weeks of study. At least 77% were compliant (ie, medicated on > or = 75% of days). Of the ITT patients, 37 did not complete 8 weeks due to insufficient response, AEs (regardless of relationship to study drug), or other reasons. Although 292 AEs occurred in 115 patients, 277 (95%) were mild to moderate and 15 (5%) were severe. Most of the AEs in these children studied during the winter were related to infectious illnesses. Only 4 serious AEs occurred; 3 were unrelated to study drug. The fourth AE--considered possibly related--was worsening sickle cell anemia 18 days after medication discontinuation. Approximately 30% of patients became asymptomatic after 8 weeks of treatment, regardless of dosing or formulation, and despite reduction of antacid use in half of the patients. No clear superiority of any dose or formulation was demonstrated. CONCLUSIONS: This large study, although limited by its open-label design and post hoc analyses, supports the tolerability and effectiveness of 8 weeks of treatment with nizatidine in children aged 5 days through 18 years. AE incidence and severity were as expected for children during the winter season. There was an overall improvement in symptoms and a decrease in antacid use. Formulation did not appear to alter tolerability or effectiveness assessments: the premade solution, extemporaneous solution, and capsule provided comparable symptomatic relief with no disproportionate adverse reactions.

Effects of antisecretory agents on angiogenesis during healing of gastric ulcers.

BACKGROUND: We studied the effects of a proton pump inhibitor (PPI) and an H2-receptor antagonist (H2-blocker) on angiogenesis during gastric ulcer healing, by examining stromal cell-derived factor (SDF-1) and CXC chemokine receptor 4 (CXCR4) expression in the gastric mucosa. METHODS: Patients with gastric ulcers were allocated to an untreated control group, consisting of patients with active ulcers (GA), healing ulcers (GH), and ulcer scars (GS) or a PPI group (P; given rabeprazole at 20 mg/day), or an H2-blocker group (H; given nizatidine at 800 mg/day). Frozen sections of biopsy specimens were examined by reverse transcription-polymerase chain reaction (RT-PCR) to analyze SDF-1 and CXCR4 mRNA. RESULTS: CXCR4 mRNA levels were elevated in the control (GH and GS patients) group and the H2-blocker group. CXCR4 was significantly elevated in the P-GA subgroup of the PPI group (P<0.01), but its level decreased with time. CONCLUSIONS: In the PPI group, CXCR4 levels were increased in the early phase of ulcer healing and returned to a level similar to that in the control group during the scar phase. These results suggest that PPIs increase the expression of CXCR4 mRNA and thus promote vessel regeneration and maturation, facilitating ulcer healing.

Effects of computerized physician order entry on prescribing practices.

BACKGROUND: Computerized order entry systems have the potential to prevent errors, to improve quality of care, and to reduce costs by providing feedback and suggestions to the physician as each order is entered. This study assesses the impact of an inpatient computerized physician order entry system on prescribing practices. METHODS: A time series analysis was performed at an urban academic medical center at which all adult inpatient orders are entered through a computerized system. When physicians enter drug orders, the computer displays drug use guidelines, offers relevant alternatives, and suggests appropriate doses and frequencies. RESULT: For medication selection, use of a computerized guideline resulted in a change in use of the recommended drug (nizatidine) from 15.6% of all histamine(2)-blocker orders to 81.3% (P<.001). Implementation of dose selection menus resulted in a decrease in the SD of drug doses by 11% (P<.001). The proportion of doses that exceeded the recommended maximum decreased from 2.1% before order entry to 0.6% afterward (P<.001). Display of a recommended frequency for ondansetron hydrochloride administration resulted in an increase in the use of the approved frequency from 6% of all ondansetron orders to 75% (P<.001). The use of subcutaneous heparin sodium to prevent thrombosis in patients at bed rest increased from 24% to 47% when the computer suggested this option (P<.001). All these changes persisted at 1- and 2-year follow-up analyses. CONCLUSION: Computerized physician order entry is a powerful and effective tool for improving physician prescribing practices.

Formulation and characterization of floating microballoons of nizatidine for effective treatment of gastric ulcers in murine model.

BACKGROUND: The purpose of the present study was to formulate and characterize Nizatidine-encapsulated microballoons for enhancing bioavailability and increasing the residence time of drug in the gastrointestinal tract. METHODS: Microballoons were prepared using emulsion solvent diffusion method using Eudragit S-100 and HPMC as the polymer. The formulation process was optimized for polymer ratio, drug: polymer ratio, emulsifier concentration, stirring speed, stirring time. Optimized formulation was subjected to scanning electron microscopy, drug entrapment, buoyancy studies, in-vitro drug release and in-vivo floating efficiency (X-ray) study. In-vivo antiulcer activity was assessed by ethanol-induced ulcer in murine model. RESULTS: The microballoons were smooth and spherical in shape and were porous in nature due to hollow core. A sustained release of drug was observed for 12 h. Examination of the sequential X-ray images taken during the study clearly indicated that the optimized formulation remained buoyant and uniformly distributed in the gastric contents for a period of 12 h. In ethanol-induced ulcer model, drug-loaded Microballoon-treated group showed significant (p < 0.01) ulcer protection index as compared to free drug-treated group. CONCLUSION: Nizatidine-loaded floating microballoons may serve as a useful drug delivery system for prolonging the gastric residence time and effective treatment of gastric ulcers.

Nizatidine versus placebo in active benign gastric ulcer disease: an eight-week, multicenter, randomized, double-blind comparison. The Nizatidine Benign Gastric Ulcer Disease Study Group.

STUDY OBJECTIVE: To determine if 150 mg nizatidine twice daily or 300 mg nizatidine at bedtime are similarly effective and to compare each dose with placebo in healing benign gastric ulcers and relieving peptic ulcer symptoms. METHODS: This study was a randomized, double-blind, placebo-controlled parallel comparison. The study was conducted at 74 gastroenterology and internal medicine clinics in the United States and Canada. Four hundred fifty-six patients with active benign gastric ulcer documented by endoscopy participated in the study. On the basis of a computer-generated randomization list, patients were assigned sequentially to receive either 150 mg nizatidine twice daily (n = 151), 300 mg nizatidine once daily at bedtime and identically appearing placebo capsules in the morning (n = 153), or placebo capsules twice daily (n = 152). Treatment lasted for 8 weeks unless healing was documented by endoscopy after 4 weeks. Antacid tablets (aluminum hydroxide, magnesium hydroxide, simethicone combination) were supplied for relief of symptoms. MEASUREMENTS AND MAIN RESULTS: Both doses of nizatidine significantly improved healing rates at 8 weeks compared with placebo. Daytime and nighttime symptom severity was improved by both nizatidine regimens at end point (p less than 0.015 versus placebo, two-tailed test). Antacid use was similar for all groups in the end point analysis. Patient well-being was significantly better in patients treated with nizatidine than in patients in the placebo group ((p less than 0.04, two-tailed test). No clinically significant differences in the incidence of adverse clinical or laboratory events were noted. CONCLUSION: Nizatidine, 300 mg at bedtime and 150 mg twice daily, resulted in greater healing of benign gastric ulcers than placebo treatment after 8 weeks. Relief of the symptoms of gastric ulcer was significantly better in the patients receiving nizatidine treatment versus placebo treatment.

Antiulcer drug prescribing in hospital successfully influenced by "immediate concurrent feedback".

OBJECTIVE: To determine whether immediate concurrent feedback (ICF) focused on inpatient omeprazole prescribing achieved more rational and cost-effective antiulcer drug prescribing and usage. METHODS: In a 1400-bed teaching hospital, an audit (by specially trained personnel) was conducted to monitor inpatient prescribing of omeprazole (1) in preference to H2-antagonists and other drugs according to agreed criteria (Helicobacter pylori eradication, severe reflux esophagitis, rapid ulcer healing deemed urgent because of severe symptoms or complications, high-dose steroid therapy of > or =30 mg/day prednisolone) and (2) appropriateness of intravenous dosing (oral route not feasible or contraindicated). After baseline monitoring for 1 month, followed by relevant antiulcer drug therapy education, ICF was instituted for 1 year. This entailed explanatory memoranda requesting a change in prescribing issued to the respective medical teams of patients whose omeprazole prescription did not "conform." The main outcomes of the study were omeprazole prescription numbers per month and the proportion conforming, defined daily doses of antiulcer drugs used and corresponding expenditures, and pertinent antiulcer drug utilization data from 9 other local hospitals. RESULTS: Baseline omeprazole prescribing conformed in 32 of 173 (18%) of the patients compared with 451 of 546 (83%) during institution of ICF (P < 0001; chi2 test). Correspondingly, average overall omeprazole and ranitidine usage (inpatient and outpatient) and expenditure decreased (44% and 45%, respectively); collectively, use of less expensive alternatives increased about 61%. Estimated savings averaged about HK$150,000 ($20,000) per month. No comparable changes in usage were noted in 9 other local hospitals. CONCLUSION: Regarding hospital antiulcer drugs, this ICF strategy was associated with more rational prescribing and usage, and an important saving of resources.

Peptic ulcer in the elderly--a double-blind, short-term study comparing nizatidine 300 mg with ranitidine 300 mg. GISU (Interdisciplinary Ulcer Study Group).

UNLABELLED: This was a randomized, double-blind, multicentre, short-term study comparing ranitidine and nizatidine at the standard dosages of 300 mg at bedtime. In 49 centres in Italy, all peptic ulcer patients aged over 65 years and with endoscopically documented acute disease were considered eligible for the study. Clinical check-ups were repeated every 3 weeks, while the endoscopic and biochemical assessments were scheduled at 6 and (in unhealed patients) 12 weeks. STATISTICS: chi-squared test, Fisher's exact test, Student t-test for unpaired data. The study included 170 duodenal ulcer and 75 gastric ulcer patients. Of these, 83/170 duodenal ulcer and 38/75 gastric ulcer patients were treated with nizatidine 300 mg and the remainder with ranitidine 300 mg. The groups were well-matched for common clinical data. Eight patients dropped out. Healing rates at 6 and 12 weeks were 81.9% and 91.5% for nizatidine-treated duodenal ulcer patients versus 78.1% and 94.2% for ranitidine-treated duodenal ulcer cases (P: N.S.); 6 and 12-week healing rates were 76.3% and 89.5% for nizatidine-treated gastric ulcer patients versus 67.6% and 83.8% for ranitidine-treated gastric ulcer patients (P: N.S.). No slow healing risk factors were found. Only minor adverse events were registered. IN CONCLUSION: ranitidine 300 mg and nizatidine 300 mg both proved effective and safe in the treatment of acute peptic ulceration in the elderly.

Effectiveness and safety of nizatidine, 75 mg, for the relief of episodic heartburn.

BACKGROUND: The most frequent cause of episodic heartburn is food and beverage ingestion. Nizatidine, an H2-receptor antagonist, is currently approved for non-prescription use in the prevention and relief of heartburn at a dose of 75 mg up to twice a day. METHODS: Two identical studies were carried out to evaluate the efficacy of nizatidine, 75 mg, compared with placebo in treating heartburn in an "at-home" setting. The studies were multicentre, multiple-dose, placebo-controlled, randomized, parallel group design. A total of 994 subjects were randomized to treatment. Adequate relief of heartburn was assessed at 15, 30 and 45 min and 1, 2 and 3 h following a treatment dose. A subject's responses with respect to time to relief and attainment of adequate relief were combined into a derived response profile, the sustained adequate relief score. Adverse experiences were noted throughout the study period. RESULTS: The individual and combined study results showed that nizatidine, 75 mg, relieved heartburn faster and/or more consistently than placebo. The mean sustained adequate relief score, calculated over a subject's first four episodes, was 2.43 in the nizatidine-treated group compared with 2.14 in the placebo group (P < 0.001). Nizatidine-treated subjects attained sustained adequate relief in a significantly (P < 0.001) larger percentage (75%) of their heartburn episodes than did subjects treated with placebo (66%). No serious adverse experiences were associated with nizatidine treatment. CONCLUSION: Nizatidine, 75 mg, is a safe and effective treatment for episodic heartburn. The results showed that subjects taking nizatidine had heartburn relief that was achieved faster and/or more reliably than did subjects taking placebo.

Nizatidine in combination with amoxycillin and clarithromycin in the treatment of Helicobacter pylori infection.

BACKGROUND: The efficacy of H2-antagonists in combination with antibiotics in curing Helicobacter pylori infection remains controversial, and it is uncertain whether double dose H2-antagonist therapy is superior to standard dose. AIM: To determine the efficacy of two doses of nizatidine in combination with two antibiotics in the treatment of H. pylori. METHODS: A randomized controlled trial was conducted in 160 patients comparing nizatidine 150 mg with 300 mg b.d. (standard vs. double dose), in combination with clarithromycin (500 mg) and amoxycillin (1000 mg) b.d. for 14 days, in Australia and Taiwan. Compliance was based on a clinical assessment and pill count. H. pylori status was determined by histology (antrum and corpus) and CLO-test. RESULTS: Baseline clinical and endoscopic findings were similar in both arms of the study. Based on an intention-to-treat analysis, cure of H. pylori was achieved in 78% (95% CI: 70.4-85.4%) in the standard nizatidine dose arm and 70% (95% CI: 61.6-78.2%) in the double dose arm (P=0.2). Similar cure rates were observed in ulcer and non-ulcer patient groups. Compliance was excellent in the single and double dose arms (85 and 91%, respectively). CONCLUSIONS: The combination of nizatidine in standard or double dose with clarithromycin and amoxycillin is similarly efficacious in curing H. pylori infection.

The bioequivalence of nizatidine (Axid) in two extemporaneously and one commercially prepared oral liquid formulations compared with capsule.

Nizatidine (Axid) is an H2-receptor antagonist used for the treatment of acid-related gastrointestinal disorders. Given the frequency of these conditions in children and the potential for pediatric use of nizatidine, an oral liquid dosage formulation would provide an alternative treatment option for patients unable to swallow solid oral dosage forms. This study was designed as an open-label, single-dose, four-way crossover trial to investigate the bioequivalence of 150 mg nizatidine administered in three oral liquid formulations (a commercially prepared oral syrup, an extemporaneous solution in apple juice, and an extemporaneous suspension in infant formula) relative to the marketed capsule formulation. Twenty-four adult subjects (ages 31.2 +/- 7.5 years; weight 71.1 +/- 11.8 kg) were enrolled, and blood samples for determination of plasma nizatidine concentrations were collected prior to drug administration and at 19 discrete intervals over a 24-hour postdose interval. Nizatidine was quantitated from plasma using a validated HPLC-MS assay, and a noncompartmental approach was used to describe nizatidine biodisposition in all subjects. Significant treatment effects were observed for log-normalized Cmax, AUC0-n, and AUC0-infinity (p < 0.001). Further evaluation revealed that nizatidine prepared in apple juice was markedly less bioavailable than the reference capsule, with 90% confidence intervals (CIs) of 0.518-0.626, 0.682-0.751, and 0.696-0.763 for Cmax, AUC0-n, and AUC0-infinity, respectively. The remaining two oral formulations demonstrated 90% CI within the guidelines established by the Food and Drug Administration (e.g., 0.80-1.25). Thus, nizatidine in infant formula and the commercially prepared oral syrup can be considered bioequivalent to the reference capsule.

Single-dose pharmacokinetics of nizatidine (Axid) in children.

The pharmacokinetics of nizatidine following a single 5.0 mg/kg oral dose given as an extemporaneous liquid formulation in apple juice was examined in 12 healthy children (8.0 +/- 2.4 years, 30.7 +/- 8.4 kg). Nizatidine and N-desmethylnizatidine were quantitated by HPLC/MS from five post dose blood samples taken over a 12-hour period. The apparent terminal elimination rate constant for nizatidine in the pediatric subjects (0.58 +/- 0.8h(-1)) was virtually identical to that (0.54 +/- 0.13 h(-1)) previously reported from adult studies. When corrected for an estimated 30% reduction in nizatidine oral bioavailability observed in adults upon coingestion of the drug with other fruit/vegetable juices, nizatidine pharmacokinetic parameter estimates (e.g., Cmax, CL/F, Vss/F) in our pediatric subjects were similar to those previously reported in adults who were administered dimensionally similar (e.g., approximately 4 mg/kg) solid oral doses of the drug. Examination of the mean area under the curve (i.e., AUC0-infinity for nizatidine and N-desmethylnizatidine suggested an approximate 15% metabolic conversion of the parent drug. Finally, nizatidine plasma concentrations in pediatric patients following a single 5.0 mg/kg oral dose exceeded the EC50 value of the drug for gastric acid suppression determined from adult studies for approximately 6 hours.

Twenty-four-hour control of gastric acidity by twice-daily doses of placebo, nizatidine 150 mg, nizatidine 300 mg, and ranitidine 300 mg.

This study was carried out to assess the effects on gastric acidity of placebo twice daily (bid), nizatidine 150 mg bid, nizatidine 300 mg bid, and ranitidine 300 mg bid by means of continuous 24-hour intragastric pH monitoring. Twelve patients with duodenal ulcer in remission were randomized to receive in single-blind fashion the above medications on four separate occasions, at least 1 week apart. The three active regimens produced higher pH values (P < .001) and maintained gastric pH above 3.0 units for a longer period (P < .001) than placebo in all time intervals but evening. Nizatidine 150 mg bid caused a lower rise in pH than nizatidine 300 mg bid (P < .01) and ranitidine 300 mg bid (P < .05) during both the daytime and the whole 24 hours. In these time windows also the time spent above 3.0 pH units was significantly shorter for the former regimen than for 300 mg bid of both nizatidine (P < .01) and ranitidine (P < .05). There was no difference between the latter two dosing schedules in terms of both potency and duration of action in all the time intervals considered. It is concluded that twice daily doses of H2 blockers are more effective than placebo in reducing gastric acidity. Three hundred milligrams twice daily of both nizatidine and ranitidine produce a significantly greater and longer-lasting acid suppression than 150 mg bid of nizatidine. Our study also confirms the greater effectiveness of H2 antagonists during nighttime than during day-time.

Influence of anti-ulcer drugs used in Japan on the result of (13)C-urea breath test for the diagnosis of Helicobacter pylori infection.

BACKGROUND: The (13)C-urea breath test (UBT) is a simple breath test for the diagnosis of Helicobacter pylori infection, but several factors have been reported to affect the results of this test. In this study, the effects of the antiulcer drugs used in Japan on the results of UBT were determined. METHODS: The subjects of the study were 64 adult volunteers who tested positive for H. pylori infection by the serum antibody method. Eight classes of anti-ulcer drugs used in Japan were administered at their usual doses to these subjects: lansoprazole, a proton pump inhibitor (PPI); nizatidine, an H(2)-receptor antagonist (H(2)RA); and polaprezinc, ecabet sodium, rebamipide, teprenone, cetraxate hydrochloride, and sucralfate, all mucoprotective agents. The study drugs were randomized for administration to the subjects, and each of the drugs was administered for 14 consecutive days. The UBT was performed on days 0, 14, and 21. RESULTS: The mean Delta(13)C per thousand in the lansoprazole group was significantly decreased on day 14, to below 10 per thousand, in 4 of 16 subjects, and in 1 of the 4 subjects, the test result was negative, with the Delta(13)C per thousand falling to 1.7 per thousand. The value returned to baseline 1 week after the discontinuation of lansoprazole. The other drugs administered had no significant effect on the result of the UBT, except that the mean Delta(13)C per thousand showed a tendency to decrease after the administration of ecabet sodium and rebamipide. CONCLUSIONS: Administration of a PPI may produce a false-negative UBT result, while other anti-ulcer drugs, for the most part, have little effect on the result of the UBT when used alone. The (13)C-urea breath test (UBT) is a simple test for the diagnosis of Helicobacter pylori infection, but several factors have been reported to affect the results of this test. In this study, the effects of the anti-ulcer drugs used in Japan on the results of the UBT were determined.

Therapeutic substitution of cimetidine for nizatidine was not associated with an increase in healthcare utilization.

OBJECTIVE: To examine changes in healthcare utilization resulting from a formulary switch to cimetidine from nizatidine at the Veterans Affairs Pittsburgh Healthcare System. STUDY DESIGN: A retrospective analysis of administrative and clinical data 6 months before and 6 months after the therapeutic substitution. METHODS: The 704 patients who were switched from nizatidine to cimetidine were included in the study. Administrative data included total and primary care clinic visits, emergency room visits, gastrointestinal (GI)-related radiological studies, and GI endoscopic procedures. Discharge summaries were examined, and rates of total and GI-related hospitalizations were calculated. RESULTS: There was no evidence of increased utilization of healthcare resources during the 6 months after the formulary switch. Estimated monthly pharmaceutical savings for the Veterans Affairs Pittsburgh Healthcare System were $7260. CONCLUSIONS: A formulary switch from nizatidine to cimetidine can be accomplished at significant pharmaceutical cost savings, and this retrospective study suggests that this can be done without increasing other aspects of healthcare resource utilization.

Chitosan microspheres prepared by spray drying.

Non-crosslinked and crosslinked chitosan microspheres were prepared by a spray drying method. The microspheres so prepared had a good sphericity and a smooth but distorted surface morphology. They were positively charged. The particle size ranged from 2 to 10 micron. The size and seta potential of the particles were influenced by the crosslinking level. With decreasing amount of crosslinking agent (either glutaraldehyde or formaldehyde), both particle size and zeta potential were increased. Preparation conditions also had some influence on the particle size. DSC studies revealed that the H2 antagonist drug cimetidine, as well as famotidine was molecularly dispersed inside the microspheres, in the form of a solid solution. The release of model drugs (cimetidine, famotidine and nizatidine) from these microspheres was fast, and accompanied by a burst effect.

Compliance with therapy for ulcer disease: clinical experience and review of the literature.

As a factor favoring relapses, noncompliance is particularly crucial to the treatment of peptic ulcer disease, and greater efforts should be made to eliminate or reduce it. To investigate the reasons for noncompliance, we performed two clinical trials involving a total of 592 patients with duodenal ulcer treated with various H 2 antagonists for 12 months. In the first study, 40.3% of patients with uncomplicated duodenal ulcer were noncompliant, compared with only 4.6% who had had previous bleeding episodes. Compliance in the second study averaged 68%. Major reasons for noncompliance among these patients were an absence of symptoms and an inconvenient dosage schedule. On the basis of our clinical experience and a review of the literature, compliance appears to be higher in patients with previous complications of their disease and when the effectiveness of prescribed drugs does not depend on ingestion with the evening meal.

The effect of a single oral morning dose of nizatidine and ranitidine on intragastric pH under basal conditions and after pentagastrin stimulation.

A comparison was made of the antisecretory activity of orally administered nizatidine and ranitidine by measuring intragastric pH under basal conditions and during and after pentagastrin stimulation. Intragastric pH values were measured with a bipolar glass electrode in 10 patients with healed duodenal ulcers treated with nizatidine or ranitidine according to a randomized single-blind design. The antisecretory activity of the two drugs was similar during the 4 h of monitoring following drug administration. Nizatidine, however, showed a more rapid inhibitory action than ranitidine, producing a significantly greater increase in pH with respect to basal values during pentagastrin infusion. In the period following infusion the pH values observed with ranitidine were higher than with nizatidine, but not significantly so. Under these experimental conditions, therefore, the antisecretory activity of nizatidine was shown to be more rapid than that of ranitidine and equally effective.