"Oxmetidine"

Role of nocturnal acid suppression on the rate of duodenal ulcer healing: clinical dose-range trials with oxmetidine. These studies represent the first attempt to compare, concurrently, several once or twice daily dosage regimens of an H2-receptor antagonist for ulcer-healing efficacy in the same national population within the same time period, using the same criteria for patient selection , duration of treatment, and end-point. Investigators from 66 centers entered 745 patients, 17-71 years of age, with endoscopically documented uncomplicated duodenal or pyloric channel ulcers, greater than or equal to 0.5 cm in the longest axis. Patients were randomly assigned to six regimens (five oxmetidine, one placebo) and were dosed once (bedtime) or twice (morning and bedtime) daily. Antacid use

Factors influencing healing of duodenal ulcer. Control of nocturnal secretion by H2 blockade and characteristics of patients who failed to heal. To study the efficacy of a single bedtime dose of H2-receptor antagonist in the healing of duodenal ulcer, a 12-week randomized double-blind controlled trial of oxmetidine, which is equipotent to cimetidine and has a similar duration of action , was performed in 80 patients. Oxmetidine, 600 mg bedtime, resulted in significantly more complete healing than placebo at weeks 2, 4, 6, 8, 10, and 12 as assessed endoscopically. At weeks 4 and 6, 72.5% and 85%, respectively, of ulcers were completely healed by oxmetidine, and 36.8% and 41.7%, respectively, by placebo. Of 45 prospectively obtained patient characteristics, high pentagastrin-stimulated maximal

A comparison of oxmetidine and cimetidine in the treatment of duodenal ulcer. Oxmetidine (1 g/day), a new histamine H2-receptor antagonist, or cimetidine (1 g/day) was given to 30 patients with endoscopically proven duodenal ulcers in a randomised, double-blind trial. Ulcer healing was assessed endoscopically after four weeks' treatment, and again at eight weeks in those who had not healed in the first four weeks. Of the 15 patients receiving oxmetidine, 11 (73 percent) had healed their ulcers in four weeks, while 14 (93 percent) had healed their ulcers in eight weeks. Comparable healing rates were found with cimetidine, namely 13 of 15 (87 percent) after four weeks and all 15 patients (100 percent) after eight weeks. The patients were relieved of their symptoms to a comparable degree

Comparative randomized, double-blind study of oxmetidine versus cimetidine for short-term treatment of duodenal and prepyloric ulceration. 101 patients with endoscopically verified duodenal or prepyloric ulcerations were treated in a 4- to 8-week double-blind randomized trial with oxmetidine 400 mg twice daily (51 patients) or cimetidine 1 g daily (50 patients). Both groups had free access to antacid tablets for symptomatic relief. There were no significant differences between the two treatment alternatives with regard to ulcer healing, relief of ulcer pain, or antacid consumption. The ulcer healing rate after 4 weeks of treatment was 80% in the oxmetidine group and 74% in the cimetidine group and, after 8 weeks, 92% and 86%, respectively. The differences in healing rate at 4 and 8 weeks

Effect of cimetidine and oxmetidine on 24-h gastric acid and pepsin in patients. The 24-h intragastric pH, titrated hydrogen ion concentration, and pepsin concentration were studied in nine peptic ulcer patients during administration of placebo and of 800 mg cimetidine given as two or four equal doses. Cimetidine, 400 mg twice daily, was more effective in reducing acidity during morning (p less histamine H2-receptor antagonist, oxmetidine, was studied in six other patients, also during a 24-h period. Both 400 mg twice daily and 200 mg four times daily of oxmetidine were superior to placebo (p less than 0.05) in reducing intragastric acidity during the entire 24-h period.

Pharmacokinetics of oxmetidine, a new histamine H2-receptor antagonist, after single oral and intravenous doses. The plasma concentration curves and urinary excretion of oxmetidine after administration of single i.v. (100 mg) and oral (200 mg) doses have been studied in 11 patients with peptic ulcer disease. The mean bioavailability of the drug was 70% (range 53-91%). After intravenous

Cimetidine, but not oxmetidine, penetrates into the cerebrospinal fluid after a single intravenous dose. 1 Thirty-six patients with various neurological diseases or symptoms received single intravenous doses of either cimetidine 400 mg (n = 19) or oxmetidine 200 mg (n = 17), 15 or 60 min before a diagnostic lumbar puncture. 2 In the 15 min CSF samples concentrations of cimetidine were detectable No detectable concentrations of oxmetidine were found either in the 15 min (n = 9) or in the 60 min (n = 8) liquor samples. 5 Cimetidine penetrates the blood-drain barrier slowly and not freely after a single dose. Our data suggest that the new histamine H2-receptor antagonist oxmetidine does not cross this barrier.

Effect of three single doses of oxmetidine administered intravenously on the volume and acidity of gastric secretion, serum prolactin and gastrin concentration in healthy volunteers. Gastric acid secretion was measured in six healthy volunteers following the intravenous administration (over 30 min.) of oxmetidine 200 mg, 400 mg and 800 mg in a randomized double blind trial for 12 hours. Gastric aspirates were fractionated into hourly aliquots and pH, volume, gastric acidity and gastric acid output were determined. Total gastric acid output over 12 hours was significantly reduced from 24.4 mmol/12 h (median) after placebo to 13.5 mmol/12 h, 11.8 mmol/12 h and 7.7 mmol/12 h after oxmetidine 200 mg, 400 mg and 800 mg respectively. An inhibition of at least 90% was achieved with all doses

Effect of smoking on duodenal ulcer healing with cimetidine and oxmetidine. The effect of oxmetidine 800 mg/day, a new histamine H2-receptor antagonist, on duodenal ulcer healing was compared with cimetidine 1000 mg/day in a two-centre double-blind trial. Ninety-nine patients completed the study. After four weeks, ulcers were healed in 74% of the cimetidine-treated patients and in 78 % of the oxmetidine-treated patients (p greater than 0.05). Healing rates after eight weeks increased to 90% in the cimetidine group and to 94% in the oxmetidine group. Healing rates after four weeks were, however, different in the two centres (p less than 0.01): in centre 1 88% of the cimetidine-treated, but 63% of the oxmetidine-treated patients healed, in centre 2 rates were 60% (cimetidine) and 92% (oxmetidine

The influence of smoking on the healing of duodenal ulcer treated with oxmetidine or cimetidine. The influence of smoking on duodenal ulcer healing was examined during a double blind study of 83 patients randomly allocated to oxmetidine or cimetidine treatment. Smoking habits were recorded but patients were not advised to change these. Smokers and nonsmokers were similar clinically and did

Double blind controlled trial with oxmetidine and cimetidine in the short-term treatment of duodenal ulcer. Clinical efficacy and safety of oxmetidine (400 mg b.i.d.), a new potent specific H2-receptor antagonist, and cimetidine (1 g/day) were compared in a double-blind randomized trial of 4 weeks duration that involved 39 outpatients with endoscopically proven active duodenal ulcer . The disappearance of the ulcer crater leading to complete reepithelization of the bulbs or to the presence of erosions occurred in 17 out of 19 (89.6%) patients treated with oxmetidine, and in 13 out of 20 (65.0%) patients treated with cimetidine (n.s.). Ulcer symptoms and antacid consumption were not different in two groups. No side effects or significant haematological or biochemical abnormalities were found

Effect of 6-hourly intermittent intravenous boluses of oxmetidine and ranitidine on gastric acidity and serum prolactin. The effect on 24-h gastric juice volume and pH of 30 min intravenous infusions of 200 and 400 mg oxmetidine and 50 mg ranitidine, administered at 6-hourly intervals, has been investigated in 12 healthy male subjects. After each infusion period a median intragastric pH greater than 5 was obtained with all active treatments, which also caused a significantly elevated 24-h median pH versus placebo. The 24-h median pH following ranitidine did not differ significantly from that after either oxmetidine treatment. There was a sharp decrease in gastric volume secretion within 2 h of infusion of each active treatment. There was no significant difference between active treatments

Oxmetidine: clinical pharmacological studies with a new H2-receptor antagonist. The gastric antisecretory effects of oxmetidine, a new H2-receptor antagonist, have been studied in 33 healthy subjects. The relative potency of oxmetidine compared with that of cimetidine depended on the route of administration and the experimental conditions. Oxmetidine intravenously infused was approximately four times as potent as cimetidine, weight for weight, in inhibiting impromidine stimulated gastric acid secretion but was twice as potent when food was used as a stimulus. After oral administration there were no differences in the weight-for-weight potency of oxmetidine and cimetidine, although oxmetidine was twice as potent on a molar basis. These apparent differences according to the route of drug

Evidence that oxmetidine inhibits transmembrane-calcium flux in cardiac and vascular tissue. Oxmetidine, at concentrations in excess of 1 X 10(-6)M, caused concentration-dependent negative inotropic and chronotropic responses in guinea-pig isolated heart preparations. Oxmetidine, at concentrations in excess of 1 X 10(-5)M, caused negative inotropic responses in guinea-pig papillary muscle preparations. The negative inotropic responses to oxmetidine were associated with shortening of the plateau phase of the action potential. Verapamil and nifedipine caused similar shortening of the plateau phase of the action potential at equivalent negative inotropic concentrations indicating that oxmetidine may also act as a calcium antagonist. In preparations partially depolarized by raising extracellular

Relaxant effect of the H2-receptor antagonist oxmetidine on guinea-pig and human airways. The effects of three different H2-receptor antagonists (cimetidine, ranitidine and oxmetidine) were tested on isolated preparations of guinea-pig trachea and human bronchus against contractions induced by acetylcholine, histamine and potassium chloride (KCl). In addition, their influence on calcium concentration-response curves in guinea-pig tracheal spirals was examined in a potassium-rich solution (30 mM). Finally, their effects were studied in vivo against acetylcholine and histamine-induced bronchoconstriction in anaesthetized guinea-pigs. In guinea-pig isolated trachea, oxmetidine--in contrast to cimetidine and ranitidine, which were completely inactive--induced a concentration-dependent relaxation

Histamine H2-antagonists modify gastric emptying in the rat. 1 Histamine H2-receptor antagonists were tested for their effect on gastric emptying in the rat. 2 At low doses all the compounds were inactive except for burimamide which delayed and ranitidine which accelerated gastric emptying. 3 At high doses burimamide, metiamide, cimetidine and oxmetidine delayed, whereas ranitidine accelerated of cimetidine- and oxmetidine-induced slowing of gastric emptying was apparently related to cholinolytic and possibly also relaxant effects of the compounds. 6 These different effects of the various H2-blockers are consistent with the idea that changes in emptying rate are independent of H2-receptor blockade.

and bepridil, which have been shown to alter the calcium dependence of myofibrillar ATPase activity and oxmetidine, an H2-receptor antagonist which binds to calmodulin, were also studied. 2. The rates of dissociation of calcium from both the regulatory and high affinity sites on bovine isolated cardiac troponin C (cTnC) were measured in a stopped-flow fluorimeter. The rates of dissociation were found of dissociation of Ca2+ from the regulatory site was slightly reduced (approximately 20%) by pimobendan (50 and 100 microM) and was somewhat increased by oxmetidine (28% at 100 microM). 4. Bepridil (25 microM) reduced the rate of dissociation by 50%, indicating a direct effect of bepridil on TnC. 5. Sulmazole, isomazole, perhexiline, pimobendan (50 microM) and bepridil (25 microM) were without effect