Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ranitidine”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Effect of single doses of cisapride and ranitidine administered simultaneously on plasma concentrations of cisapride and ranitidine.

We have studied in 12 volunteers the effect of single doses of cisapride and ranitidine, administered simultaneously, on plasma concentrations of cisapride and ranitidine. Median maximum plasma concentration of ranitidine was achieved 1 h earlier when ranitidine was taken with cisapride compared with ranitidine alone (P = 0.012). There was a 24% decrease in plasma ranitidine AUC8h when ranitidine was taken with cisapride compared with ranitidine alone (P less than 0.005). Ranitidine had no effect on absorption of cisapride.

Adult↗

Double blind multicentre comparison of omeprazole 20 mg once daily versus ranitidine 150 mg twice daily in the treatment of cimetidine or ranitidine resistant duodenal ulcers.

The purpose of the present study was to compare omeprazole 20 mg once daily and ranitidine 150 mg twice daily in healing duodenal ulcers unhealed by previous treatment with cimetidine greater than or equal to 0.8 g or ranitidine greater than or equal to 0.3 g daily for at least six weeks. In a double blind multicentre trial, 151 patients were randomly assigned to either omeprazole or ranitidine. Clinical assessments and endoscopies were carried out at two and four weeks. Patients characteristics were similar in both groups. Statistical analysis (chi 2 test) did not show any significant difference in healing rate (p greater than 0.20) irrespective of the method of calculation. On an 'intent-to-treat' analysis (n = 151), healing was: omeprazole 46.6%, ranitidine 43.3% at day 15 and omeprazole 70.7%, ranitidine 68.4% at day 29; and among the patients who completed treatment, healing was: omeprazole 48.3%, ranitidine 46.3% at day 15 (n = 125; 95% confidence interval of the difference--17 to 21) and omeprazole 79.6%, ranitidine 75.4% at day 29 (n = 115; 95% confidence interval of the difference--13 to 21). After a further four weeks treatment with omeprazole, healing occurred in 16/20 (80%) who still had active disease at day 29. Patients on omeprazole and on ranitidine experienced similar decrease in day time and night time epigastric pain and in heartburn. Multivariate analysis (logistic regression) did not indicate any influence on age, sex, smoking and alcohol habits, previous drug administered, duodenitis and duodenal erosions on the healing rate. In this model, healing rate was not significantly influenced by previous treatment duration (p = 0.09 at day 15 and p greater than 0.2 at day 29) but was significantly influenced by ulcer size (p = 0.04 at day 15 and p = 0.02 at day 29). Forty one patients complained of adverse events: 19 on omeprazole (four trial withdrawals), 22 on ranitidine (three trial withdrawals).

Adult↗

Pharmacokinetics of bismuth and ranitidine following multiple doses of ranitidine bismuth citrate.

1. The pharmacokinetics of bismuth and ranitidine derived from oral doses of ranitidine bismuth citrate 800 mg given twice daily for 28 days were examined in this double-blind, placebo-controlled, parallel-group study in 27 healthy subjects. 2. Bismuth accumulation in plasma reflected its multicompartmental disposition, achieving the majority of predicted steady state within 14-28 days. Bismuth absorption from ranitidine bismuth citrate is limited (< 0.5% of the dose), and bismuth elimination is predominantly renal secretion. Peak plasma concentrations did not exceed 19 ng ml-1, remaining well below those associated with bismuth toxicity. Bismuth was measurable at low concentrations in plasma and urine for up to 5 months after the last dose. Plasma bismuth concentration-time data and urinary excretion data were best described by separate multicompartmental models, with terminal half-lives averaging 21 days and 45 days, respectively. 3. The pharmacokinetics of ranitidine derived from ranitidine bismuth citrate were similar to those of ranitidine administered alone. Ranitidine did not appreciably accumulate in plasma. 4. Ranitidine bismuth citrate was well-tolerated during 28 days of repeated dosing.

Adult↗

Ranitidine bismuth citrate and ranitidine do not affect gastric emptying of a radio-labelled liquid meal.

Ranitidine bismuth citrate, a new chemical entity which is a salt complex of ranitidine and bismuth citrate, is being developed for the treatment of relapse of benign gastric and duodenal ulcer and eradication of Helicobacter pylori. The aim of the present study was to establish whether ranitidine bismuth citrate (800 mg) or ranitidine hydrochloride (300 mg) have any effect on gastric emptying of a liquid meal using gamma scintigraphy. On three separate occasions, each of twelve subjects received a single oral tablet of 800 mg ranitidine bismuth citrate, 300 mg ranitidine hydrochloride or placebo in random order. Thirty minutes after dosing each subject was given 375 ml of 99mTc-DTPA (diethylene triaminepentaacetic acid) labelled Clinifeed-ISO. The primary endpoint was the time to 50% gastric emptying (t50%). The proportion of the meal remaining was summarised by weighted mean proportion of the meal remaining in the stomach over 0-60 min and 0-180 min, separately. No differences were observed for t50%, weighted mean 0-60 min, and weighted mean 0-180 min between any two treatments. In man, we have detected no significant effect of single oral doses of ranitidine bismuth citrate 800 mg or ranitidine hydrochloride 300 mg on the rate of gastric emptying of a liquid meal when compared with placebo.

Adult↗

Pharmacodynamic effects of 3-day intravenous treatment with pantoprazole or ranitidine after 10 days of oral ranitidine.

Tachyphylaxis (drug tolerance) is an undesirable condition in drug therapy with histamine-2-receptor antagonists (H2RAs). The concept of overcoming tachyphylaxsis via intravenous (i.v.) administration of proton-pump inhibitors (PPIs) or H2RAs is of significant interest to physicians. In the present study, 32 healthy Helicobacter pylori negative male volunteers were evaluated for the ability of i.v. pantoprazole or i.v. ranitidine to overcome oral ranitidine tachyphylaxis. After 10 days of oral treatment with enteric-coated 300-mg ranitidine tablets once daily in the evening, two groups of 16 volunteers each were randomized to receive either i.v. pantoprazole or i.v. ranitidine for up to 72 h. The primary variable was defined as the increase in 24-h gastric pH median after 1 day of i.v. treatment; the secondary variable was median percentage of time that 24-h gastric pH was <4, as calculated by Hodges-Lehman shift estimators. After 10 days of oral ranitidine treatment, tachyphylaxis was present in all volunteers. Within 1 day of continuous i.v. pantoprazole or i.v. ranitidine administration, 24-h median gastric pH increased from pH 1.45 to pH 3.50 (241%) and from pH 1.50 to pH 2.35 (157%), respectively. I.v. pantoprazole was found to be significantly more effective (p<0.05) than i.v. ranitidine in increasing the 24-h gastric pH after oral ranitidine tachyphylaxis.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Ranitidine (Zantac) syrup versus Ranitidine effervescent tablets (Zantac) EFFERdose) in children: a single-center taste preference study.

BACKGROUND: The histamine H(2) receptor antagonist ranitidine is US FDA-approved for the treatment of gastroesophageal reflux disease and healing of erosive esophagitis in children >or=1 month of age. A low-dose strength of ranitidine is now available in a citrus-flavored 25 mg effervescent tablet (dissolved in 5 mL of water); this formulation was developed to facilitate use in infants and smaller children. Ranitidine syrup is available in a peppermint-flavored 15 mg/mL formulation. OBJECTIVE: To compare taste preferences for ranitidine (Zantac) syrup and ranitidine effervescent tablets dissolved in water (Zantac EFFERdose) in healthy children aged 4-8 years and their adult caregivers. STUDY DESIGN AND METHODS: A randomized, single-blind, crossover, taste test trial was conducted in 102 children and 102 parents/legal guardians. All subjects received a single 45 mg dose of each formulation. After tasting both preparations children were asked: "Now that you have tasted both medicines, which one of these medicines do you think tastes better?" Adults were asked four questions to assess whether they would administer the medication to the children. RESULTS: Seventy-one percent (72/102) of the children preferred the taste of the ranitidine effervescent tablets compared with 29% (30/102) who preferred the syrup (p < 0.001). The majority of adults (71%) responded that they would prefer to administer the effervescent formulation based on taste. Adverse events consistent with product labeling were mild and were reported in four children and three adults: headache (n = 3), drowsiness (n = 1), abdominal pain/cramps (n = 2), and bloating/gas (n = 1). CONCLUSION: The taste of the ranitidine effervescent formulation dissolved in water is preferred over the ranitidine syrup. Better taste acceptance may facilitate ease of administration and compliance in pediatric patients.

Adult↗

Ranitidine 300 mg at bedtime is effective for gastric ulcers: a 12-wk, multicenter, randomized, double-blind, placebo-controlled comparison. The Ranitidine 300 mg HS Gastric Ulcer Study Group.

Ranitidine 150 mg twice daily is effective for the treatment of gastric ulcers. We proposed that ranitidine 300 mg once daily would also be effective. In a randomized, double-blind, placebo-controlled, multicenter, parallel-group study, adults with an endoscopically verified acute gastric ulcer > or = 5 mm were treated with either ranitidine 300 mg (n = 183) or placebo (n = 178) at bedtime for up to 12 wk. Gastric ulcer healing, determined by endoscopy, was achieved in 65% and 89% of ranitidine-treated patients by 6 and 12 wk, compared with 45% and 72% of placebo-treated patients by 6 wk and 12 wk (p < 0.001). Throughout the 12-wk study, ranitidine 300 mg was significantly more effective than placebo in relieving pain (p < 0.05), with ranitidine-treated patients also using fewer antacid tablets. Ranitidine 300 mg had a safety profile similar to that of placebo. We conclude that ranitidine 300 mg at bedtime is safe and effective for healing acute gastric ulcers.

Acute Disease↗

Early evening dosing of ranitidine. Comparison with nighttime dosing of ranitidine or cimetidine in duodenal ulceration.

A double-blind multinational comparison of ranitidine 300 mg post evening meal (pem), ranitidine 300 mg nocte and cimetidine 800 mg nocte has been carried out in 1677 patients with endoscopically verified duodenal ulcer disease. Fifty-three percent of ulers healed by two weeks during treatment with ranitidine 300 mg pem and 88% by four weeks, while the results for ranitidine 300 mg nocte were 50% and 86%, respectively, and 44% and 84% for cimetidine. The difference between ranitidine 300 mg pem and cimetidine was significant at two weeks (P = 0.002, Mantel-Haenszel chi-squared test). The relative efficacy of the treatments was not dependent upon gender, smoking habit, alcohol intake, or ulcer frequency. However, the overall differences in healing between patients with small and large ulcers and patients with single and multiple ulcers were significantly different at weeks 2 and 4 (P < 0.001). Significantly more patients treated with ranitidine (60%) had complete relief of epigastric pain than those treated with cimetidine (54%) (P < 0.05). A meta-analysis of the four double-blind comparisons of ranitidine 300 mg pem (N = 841) and 300 mg nocte (N = 849), including the present study, failed to show the benefits of pem dosing, predicted from pharmacological studies.

Adult↗

Pharmacokinetics of bismuth and ranitidine following single doses of ranitidine bismuth citrate.

1. The pharmacokinetics of bismuth and ranitidine derived from ranitidine bismuth citrate given in single oral doses ranging from 200 mg to 1600 mg were evaluated in healthy subjects. 2. Bismuth was only minimally absorbed (< 0.5% of the amount dosed) after administration of ranitidine bismuth citrate, and peak plasma concentrations never exceeded 33 ng ml-1 in any subject. Plasma concentrations and urinary recoveries of bismuth at doses up to and including 800 mg were relatively constant and not proportional to dose. Bismuth absorption was increased more than proportionally with the dose at 1600 mg. 3. The pharmacokinetics of ranitidine after administration of ranitidine bismuth citrate were dose-proportional and consistent with previous observations for ranitidine administered alone. 4. Ranitidine bismuth citrate was well-tolerated in single oral doses of up to 1600 mg.

Adult↗

Acute treatment of reflux oesophagitis: a multicentre trial to compare 150 mg ranitidine b.d. with 300 mg ranitidine q.d.s.

H2-receptor antagonists administered in conventional dosage regimens fail to heal a significant proportion of patients with moderate or severe reflux oesophagitis. We have compared the effects of a higher dose of ranitidine (300 mg q.d.s.) with the currently recommended dosage regimen (150 mg b.d.) in 138 patients suffering from reflux oesophagitis. After 4 weeks of treatment 29% of patients who received 150 mg ranitidine b.d., and 63% of patients who received 300 mg ranitidine q.d.s. had complete endoscopic healing of their lesions (P less than 0.0001). After 8 weeks these proportions had increased to 54% and 75%, respectively (P less than 0.01). After 4 weeks of treatment, compete symptomatic relief had been achieved in 46% of patients who received 150 mg ranitidine b.d. and in 67% of patients who received 300 mg ranitidine q.d.s. (P less than 0.05). After 8 weeks these proportions were 64% and 84%, respectively (P less than 0.05). Both dosage schedules were well-tolerated. We conclude that more rapid symptom relief and healing in reflux oesophagitis can be achieved with 300 mg ranitidine q.d.s. than with 150 mg ranitidine b.d.

Acute Disease↗

[Acute toxicity of ranitidine and its metabolite in mice, rats and rabbits, and subacute oral toxicity of ranitidine in rats].

Acute and subacute toxicities of ranitidine hydrochloride, a new histamine H2-receptor antagonist, and acute toxicity of ranitidine N-oxide, a metabolite of ranitidine hydrochloride, were investigated. The results are summarized as follows: (1) Oral, intravenous, subcutaneous, intraperitoneal and intramuscular LD50 values of ranitidine hydrochloride in 5- and 12-weeks old mice and rats and 12-weeks old rabbits were ranged from ca. 60 mg/kg (12-weeks old male mice, i.v.) to 6610 mg/kg (12-weeks old male rats, p.o.). In comparison of the LD50 values, it was revealed that female rats were more sensitive to the drug than males in the case of oral administration. (2) A single intravenous injection with ranitidine N-oxide at a dose of 1000 mg/kg, induced no lethal cases in mice, indicating that the N-oxide has very low toxicity in a comparison with that of ranitidine hydrochloride. (3) In the subacute toxicity test, male and female rats were orally administered with ranitidine hydrochloride for 35 days. Dose dependent changes such as increase in liver weight and water consumption, decrease in spontaneous movement and others were induced at doses of more than 500 mg/kg/day in females and 1000 mg/kg/day in males. These results indicate that the no effects were observed at levels of 250 mg/kg/day in females and 500 mg/kg/day in males. In the recovery test, however, no marked changes were observed in the rats which had been administered at 1000 and 2000 mg/kg/day for 35 days.

Administration, Oral↗

Ranitidine for non-ulcer dyspepsia. A clinical study of the symptomatic effect of ranitidine and a classification and characterization of the responders to treatment.

Seven Norwegian centres recruited 61 female and 54 male patients with non-ulcer dyspepsia (NUD). Their mean age was 40 years. After 6 weeks' double-blind alternating treatment with 150 mg ranitidine twice daily and placebo, 1 week of each alternative (part I), an effect score (Xs) and an efficacy index (Ei) were calculated. Ranitidine was significantly superior to placebo for symptomatic relief (p less than 0.01). Twenty-eight, 49, and 38 patients were Xs-classified as 'responders', 'unclassified', and 'nonresponders' to ranitidine, respectively. The symptomatic effect was impressive in the responder group and moderate but significant also in the unclassified group. The nonresponders had a significantly unfavourable effect of ranitidine compared with placebo. The Xs-classified responders and unclassified continued single-blind treatment with ranitidine for 4 weeks (part II) and were reclassified as 'new responders/nonresponders'. The new responders received single-blind treatment with placebo until relapse or maximum 8 weeks (part III). Parts II and III verified the good Xs classification of responders to ranitidine treatment. The overall effect of ranitidine in patients with NUD was due to good symptomatic effect in a subpopulation characterized by meal-related heartburn and/or regurgitation, large body mass index, first-degree relatives with gastrointestinal diseases, a relatively low frequency of gastrointestinal symptoms per week, and absence of soft stools.

Adult↗

A comparison of omeprazole with ranitidine for ulcers associated with nonsteroidal antiinflammatory drugs. Acid Suppression Trial: Ranitidine versus Omeprazole for NSAID-associated Ulcer Treatment (ASTRONAUT) Study Group.

BACKGROUND: Suppressing acid secretion is thought o reduce the risk of ulcers associated with regular use of nonsteroidal antiinflammatory drugs (NSAIDs), but the best means of accomplishing this is uncertain. METHODS: We studied 541 patients who required continuous treatment with NSAIDs and who had ulcers or more than 10 erosions in either the stomach or duodenum. Patients were randomly assigned to double-blind treatment with omeprazole, 20 mg or 40 mg orally per day, or ranitidine, 150 mg orally twice a day, for four or eight weeks, depending on when treatment was successful (defined as the resolution of ulcer and the presence of fewer than five erosions in the stomach, and fewer than five erosions in the duodenum, and not more than mild dyspepsia). We randomly assigned 432 patients in whom treatment was successful to maintenance treatment with either 20 mg of omeprazole per day or 150 mg of ranitidine twice a day for six months. RESULTS: At eight weeks, treatment was successful in 80 percent (140 of 174) of the patients in the group given 20 mg of omeprazole per day, 79 percent (148 of 187) of those given 40 mg of omeprazole per day, and 63 percent (110 of 174) of those given ranitidine (P<0.001 for the comparison with 20 mg of omeprazole and P=0.001 for the comparison with 40 mg of omeprazole). The rates of healing of all types of lesions were higher with omeprazole than with ranitidine. During maintenance therapy, the estimated proportion of patients in remission at the end of six months was 72 percent in the omeprazole group and 59 percent in the ranitidine group. The rates of adverse events were similar between groups during both phases. Both medications were well tolerated. CONCLUSIONS: In patients with regular use of NSAIDs, omeprazole healed and prevented ulcers more effectively than did ranitidine.

Adult↗

Comparison of pirenzepine, ranitidine, and pirenzepine-ranitidine combination for reducing preoperative gastric fluid acidity and volume in children.

We conducted a two-part controlled study to evaluate the efficacy of preoperative oral pirenzepine (muscarinic receptor antagonist known to inhibit gastric secretion), ranitidine, and the combination pirenzepine-ranitidine in controlling gastric fluid pH and volume in 210 ASA I children, aged 2-14 yr, undergoing elective surgery. In the first part of the study (n = 90), the proportion of children considered at risk for aspiration pneumonitis was reduced with pirenzepine 25 mg (P < 0.05) but not with 12.5 mg. In the second part of the study, the other 120 children were allocated randomly to one of four groups: pirenzepine 25 mg with placebo; ranitidine 75 mg with placebo; pirenzepine 25 mg with ranitidine 75 mg; and placebo and placebo. These medications were administered 1 h before anaesthesia. After tracheal intubation, volume and pH of the gastric fluid aspiration via a multiorifice orogastric tube were measured. Pirenzepine 25 mg decreased gastric fluid volume (P < 0.05) but failed to increase gastric pH. Ranitidine 75 mg increased gastric pH (P < 0.05) but failed to decrease fluid volume. The pirenzepine-ranitidine combination reduced gastric fluid acidity and volume (P < 0.05).

Adolescent↗

Impact of multiple risk factors and ranitidine prophylaxis on the development of stress-related upper gastrointestinal bleeding: a prospective, multicenter, double-blind, randomized trial. The Ranitidine Head Injury Study Group.

OBJECTIVES: To evaluate the impact of risk factors on the development of stress-related upper gastrointestinal bleeding in severe head injury patients randomized to treatment with a 6.25 mg/hr continuous ranitidine infusion or placebo. DESIGN: Prospective, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. SETTING: Ten intensive care units in the United States. PATIENTS: Patients with severe head injury, defined as having a Glasgow Coma Score of < or = 10, were eligible for enrollment. INTERVENTIONS: Ranitidine 6.25 mg/hr or saline placebo was administered by continuous infusion for a maximum of 5 days. MEASUREMENTS AND MAIN RESULTS: Patients were evaluated every 8 hrs for the presence of stress-related upper gastrointestinal bleeding. Bleeding developed in 15 (19%) of 81 placebo-treated patients vs. three (3%) of 86 ranitidine-treated patients (p = .002). None of the individual risk factors had a significant effect on bleeding frequency. No bleeding occurred in the four patients with one risk factor. Placebo bleeding rates in patients with 2, 3 to 5, and > 5 risk factors were 20%, 20%, and 18%, respectively. For the ranitidine-treated patients, bleeding was reported in 0%, 5%, and 0% in the 2, 3 to 5, and > 5 risk factor subgroups, respectively. Pneumonia occurred in 19% of the placebo-treated patients vs. 14% in the ranitidine treatment group. CONCLUSIONS: The full risk to develop stress-related upper gastrointestinal bleeding was realized when two risk factors were present concomitantly. The presence of additional risk factors did not increase the occurrence of bleeding. A continuous infusion of ranitidine at 6.25 mg/hr provided significant protection from bleeding, regardless of the number of risk factors present.

Adult↗

A single nighttime dose of ranitidine 300 mg versus ranitidine 150 mg twice daily in the acute treatment of duodenal ulcer: a European multicenter trial.

Six hundred and five patients with endoscopically diagnosed duodenal ulcer were randomly allocated to treatment with ranitidine 300 mg at night or ranitidine 150 mg twice daily in a prospective double-blind multicenter trial conducted in nine European countries. Endoscopy at 4 weeks showed complete ulcer healing in 246 of 301 patients (82%) treated with ranitidine 150 mg b.i.d. and 230 of 304 patients (76%) treated with ranitidine 300 mg at night. Cumulative healing rates at 8 weeks were 95 and 94% respectively. Both treatment regimens were equally effective at rapidly reducing the incidence of ulcer-related symptoms. Adverse events were few and consistent with those reported in previous studies with ranitidine 150 mg twice daily. The results of this trial indicate that a single nighttime dose of ranitidine is an effective and safe alternative to the twice daily regimen in the acute treatment of duodenal ulcer.

Adult↗

Acute treatment of reflux oesophagitis: a multicentre study to compare 150 mg ranitidine twice daily with 300 mg ranitidine at bedtime.

A randomized, double-blind, clinical trial was undertaken to compare 150 mg ranitidine b.d. with 300 mg ranitidine nocte in the treatment of reflux oesophagitis. Endoscopy data were evaluable for 336 patients after 8 weeks of treatment. At this time 75% of patients who received 150 mg ranitidine b.d., and 73% of those who received 300 mg nocte, had healed or showed endoscopic improvement to grade I oesophagitis. At 12 weeks these rates had increased to 89 and 88%, respectively. Oesophageal biopsies from 258 patients at 8 weeks showed histological improvement in 44 and 47% of those treated with 150 mg ranitidine b.d. and 300 mg ranitidine nocte, respectively. After 12 weeks histological improvement was apparent in 57 and 54% of biopsies from each group, respectively. Symptom severity and frequency was reduced to a similar extent by both treatments. Adverse events were reported by 15 patients. A 300-mg bedtime dose of ranitidine was found to be a well-tolerated, effective alternative to twice daily treatment in reflux oesophagitis.

Adult↗

Acute treatment of duodenal ulcer: a multicentre study to compare ranitidine 150 mg twice daily with ranitidine 300 mg once at night.

A randomised double blind clinical trial was undertaken in the UK and Ireland to compare ranitidine 300 mg given as a single bed time tablet with ranitidine 150 mg twice daily in the acute treatment of duodenal ulcers. Of the 594 patients with endoscopically diagnosed duodenal ulcer entered into the trial, 424 patients had complete endoscopic findings on which healing rates at four weeks were determined. By this time 156 of 201 (78%) patients healed with ranitidine 300 mg nocte compared with 186 of 223 (83%) receiving ranitidine 150 mg twice daily (p = 0.28). After eight weeks of treatment 97% of the patients in each group were healed. The healing rates for smokers and non-smokers did not differ significantly at either four or eight weeks. Each regimen was equally effective in reducing day and night-time pain. Adverse events were reported in 23 patients overall; 12 were withdrawn from the trial. Minor abnormalities in liver function tests were noted in three patients. The trial confirmed that a single dose of ranitidine 300 mg given at night is a safe, effective alternative treatment to ranitidine 150 mg bd for the acute treatment of duodenal ulcer.

Clinical Trials as Topic↗