A trial of lansoprazole in refractory gastric ulcer.

BACKGROUND: The proton-pump inhibitor, lansoprazole, a more potent gastric acid inhibitor with a longer action than H2-receptor antagonists, should heal refractory gastric ulcers more effectively. METHODS: Lansoprazole's efficacy in healing refractory gastric ulcer(s) (i.e. after 6 weeks of treatment with H2-receptor antagonists, antacids or sucralfate at recommended dosages, and/or a relapse within 1 year of documented gastric ulcer), was compared by a two-dose regimen in a four- centre, randomized, parallel group study. One hundred and eighteen patients (59 per group) with an endoscopically confirmed gastric ulcer > or = 3 mm, received lansoprazole 30 or 60 mg daily. We assessed efficacy endoscopically at 4 and 8 weeks, and again after documented healing during a maintenance phase of lansoprazole 30 mg/day at 2 and 4 months. RESULTS: Demographic and anthropometric data were comparable. Healing rates at 4 weeks were 63% (30 mg) vs. 66% (60 mg) (95% CI, -14 to 21%) and cumulatively at 8 weeks, 83% (30 mg) vs. 81% (60 mg) (95% CI, -12 to 16%). Two and 4 months after documented healing, 86% and 78% of intention-to-treat patients remained in remission. CONCLUSION: Lansoprazole 30 or 60 mg/day appear equally effective in healing refractory gastric ulcers, while maintenance therapy of 30 mg/day effectively prevented an ulcer relapse.     

Omeprazole in peptic ulcers resistant to histamine H2-receptor antagonists

Eighteen patients with duodenal, gastric or jejunal ulcers, resistant to at least 3 months treatment with histamine H2-receptor antagonists, singly or in combination with other anti-ulcer drugs, were treated with 40 mg omeprazole once daily for up to 8 weeks. All ulcers healed, the majority within two weeks. After ulcer healing patients were given maintenance therapy with high doses of cimetidine or ranitidine. Of 15 patients on maintenance therapy with H2-receptor antagonists, 12 (80%) developed a relapse after a period ranging from 3 to 52 weeks. Two patients were lost to follow-up. After re-healing on 40 mg omeprazole, two patients were given 20 mg omeprazole daily as maintenance therapy but relapses occurred again after 14 and 26 weeks respectively. After re-healing on 40 mg omeprazole, these two patients and one additional patient received maintenance therapy with 40 mg omeprazole daily. At present these three patients have been relapse-free for periods varying from 16 to 52 weeks. No side effects were registered during treatment with omeprazole. It is therefore concluded that omeprazole is highly effective in healing refractory peptic ulcers and that omeprazole maintenance therapy may be useful for prevention of relapse. Patients are sometimes seen with peptic ulceration which appears resistant to therapy with histamine H2-receptor antagonists, colloidal bismuth subcitrate, sucralfate or pirenzepine, either given as monotherapy for a prolonged period of time or as combination therapy. Usually the reason for such therapeutic failure remains obscure. Whether virtually total abolition of acid secretion will allow ulcer healing in these circumstances is unknown.(ABSTRACT TRUNCATED AT 250 WORDS)     

Omeprazole in the treatment of peptic ulcers resistant to H2-receptor antagonist

Thirty patients with peptic ulcers resistant to at least 8 weeks of continuous therapy with full-dose H2-receptor antagonists alone or followed by other anti-ulcer drugs, were treated with the gastric proton pump inhibitor omeprazole (40 mg), administered orally once daily for up to 8 weeks. The study design was non-comparative and open; healing was verified by endoscopy. After only 2 weeks of treatment, 21 out of 23 (91%) duodenal ulcer patients were healed, as well as 2 out of 2 patients with both duodenal and gastric ulcer and 1 out of 3 patients with prepyloric ulcer. After 4 weeks, all duodenal ulcers, 1 out of 2 gastric ulcers and 2 out of 3 pre-pyloric ulcers were healed. A further month of therapy healed the gastric ulcer to give an overall healing rate of 97% and leaving only one patient (pre-pyloric ulcer) unhealed at the end of the study. Of 19 patients suffering ulcer symptoms at entry, only two patients reported any symptoms at 2 weeks and one of these (who remained unhealed) continued to have symptoms throughout the study. One patient reported mild asthenia; otherwise, no clinical or biochemical side-effects were recorded. It is concluded that omeprazole is highly effective in healing refractory peptic ulcers.     

The rationale of acid suppression in the treatment of acid-related disease.

Acid-related disorders such as gastric and duodenal ulcers and gastro- oesophageal reflux disease have a high prevalence. Traditionally, acid suppression has proved to be the most effective means by which to heal these disorders, but relapse rates are high after cessation of treatment. Recently, Helicobacter pylori infection has been shown to modify several aspects of gastric function. Eradication of H. pylori infection virtually abolishes duodenal ulcer recurrence, implicating this organism in the pathogenesis of peptic ulcers and initiating a whole new strategy in the management of these acid-related disorders. More potent degrees of acid suppression result in faster healing. Moderate acid suppression, as occurs with H2-receptor antagonists, can heal just as many ulcers if treatment is continued for longer. The combination of proton pump inhibitors and antibiotics have successfully eradicated H. pylori in duodenal ulcer patients. Both H2-receptor antagonists and the proton pump inhibitors have satisfactory safety profiles. Due to their superiority in symptom relief, and in the healing of duodenal and gastric ulcers and erosive oesophagitis, and due to their ability to eradicate H. pylori infection in combination with antibiotics, the proton pump inhibitors will probably become accepted as first-line therapy for the treatment of acid-related diseases.     

Enprostil. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in the treatment of peptic ulcer disease

Enprostil, a synthetic analogue of prostaglandin E2, is effective in the treatment of patients with duodenal or gastric ulcers. As demonstrated in pharmacological studies in healthy volunteers and in patients with inactive ulcer disease, gastric acid secretion is suppressed by up to 80% for almost 12 hours after single doses of enprostil. The drug also reduces the secretion of pepsin, another 'aggressive' factor in peptic ulcer disease. Interestingly, in contrast to the H2-receptor antagonists, which either increase or have no effect on serum gastrin concentrations, enprostil inhibits basal and postprandial gastrin release. Although the possible effects of enprostil on 'defensive' factors in peptic ulcer disease-which are thought to protect the mucosa-require much further clarification, some evidence obtained in man indicates that bicarbonate secretion is enhanced by enprostil. Further, data from animal studies suggest that microvascular integrity may be preserved by a direct action of enprostil on the gastric mucosa. In healthy volunteers, the administration of enprostil in antisecretory doses protects the gastric mucosa against of enprostil in antisecretory doses protects the gastric mucosa against aspirin-induced injury. Cumulative rates of ulcer healing observed in patients with duodenal ulcers after 4 weeks' treatment with enprostil 35 micrograms twice daily were about 50 to 80%, which were similar to those seen in comparative trials with usual therapeutic doses of cimetidine or pirenzepine, but less than occurred with ranitidine. Moreover, enprostil has been shown to relieve daytime pain in a similar percentage of patients as do these H2-receptor antagonists, but night-time pain appears to respond less well to therapy with the prostaglandin. As evidenced by a few controlled trials in patients with gastric ulcers, treatment with enprostil 35 micrograms twice daily for 6 weeks provides ulcer healing in parallel with pain relief as effectively as cimetidine and ranitidine in a high percentage of patients (about 80% after 6 weeks). Prophylactic treatment with enprostil after initial ulcer healing has reduced the rate of duodenal ulcer relapse in patients 'at risk', but to a lesser extent than has ranitidine. Gastrointestinal symptoms-abdominal cramping and pain, flatulence, nausea and notably, diarrhoea-are the most frequently reported side effects during therapy with enprostil. Diarrhoea occurs in about 10% of patients, but is rarely of a severity necessitating treatment discontinuation.(ABSTRACT TRUNCATED AT 400 WORDS)     

Lansoprazole: pharmacokinetics, pharmacodynamics and clinical uses

Lansoprazole (Prevacid, TAP Pharmaceuticals, Inc.) is a substituted benzimidazole that inhibits gastric acid secretion. This agent is approved for the short-term treatment of erosive reflux oesophagitis, active gastric ulcer, active duodenal ulcer and the treatment of non-steroidal anti-inflammatory drug (NSAID)-induced gastric and duodenal ulcers. It is also approved for the long-term treatment of healed reflux oesophagitis, healed duodenal ulcer, the treatment of hypersecretory conditions such as Zollinger-Ellison syndrome and the eradication of Helicobacter pylori as a component of triple therapy with lansoprazole, clarithromycin and amoxicillin, or dual therapy with lansoprazole and amoxicillin. Its mechanism of action is to selectively inhibit the membrane enzyme H+/K+ ATPase in gastric parietal cells. In clinical trials, lansoprazole is more effective than placebo or histamine (H2)-receptor antagonists in the treatment of reflux oesophagitis. Lansoprazole administered at a dose of 30 mg daily produced faster relief of symptoms and superior healing rates in patients with gastric or duodenal ulcers or reflux oesophagitis than H2-receptor antagonists. A daily dose of 30 mg lansoprazole reduced epigastric pain faster than omeprazole 20 mg daily in patients with peptic ulcer disease but healing rates at 4 and 8 weeks were similar with both agents at these dosages. Lansoprazole was more effective than H2-receptor antagonists in patients with Zollinger-Ellison syndrome and produced similar treatment outcome to omeprazole. Lansoprazole in combination with clarithromycin and amoxicillin produced similar rates of eradication of H. pylori. In clinical trials, lansoprazole is well-tolerated and has a low frequency of side effects similar to that of H2-receptor antagonists or omeprazole.     

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

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

Famotidine. Pharmacodynamic and pharmacokinetic properties and a preliminary review of its therapeutic use in peptic ulcer disease and Zollinger-Ellison syndrome

Famotidine is a new histamine H2-receptor antagonist. On a weight basis, famotidine is 20 times more potent than cimetidine and 7.5 times more potent than ranitidine in inhibiting basal and pentagastrin-stimulated gastric acid secretion in humans. Therapeutic trials have shown that famotidine 20 mg twice daily or 40 mg at bedtime may be an effective alternative to standard doses of cimetidine for healing gastric ulcers and to standard doses of cimetidine and ranitidine for healing duodenal ulcers. When used prophylactically, a single 20 mg dose of famotidine at night decreases the incidence of duodenal ulcer recurrence (versus placebo). However, further study is needed to clarify the comparative efficacy of the H2-receptor antagonists, in particular as maintenance therapy for healed peptic ulcer. Preliminary results in a few patients with Zollinger-Ellison syndrome indicate that famotidine, alone or in combination with an anticholinergic agent, gives good control of gastric acid hyperacidity with no evidence of biochemical or haematological toxicity. Famotidine appears to be well tolerated. Unlike cimetidine, it does not have antiandrogenic effects or alter hepatic metabolism of drugs. However, wider clinical experience with famotidine is needed to accurately determine its relative tolerability compared with other anti-ulcer drugs. Thus, famotidine appears to be a suitable and well tolerated alternative to cimetidine and ranitidine for healing peptic ulcers, but wider clinical experience is needed to assess its relative efficacy and tolerability in the long term maintenance treatment of patients with healed ulcers as well as in patients with Zollinger-Ellison syndrome.     

Lansoprazole. A review of its pharmacodynamic and pharmacokinetic properties and its therapeutic efficacy in acid-related disorders.

Lansoprazole is an effective acid pump inhibitor acting at the final enzymatic step of the acid secretory pathway of the parietal cell, decreasing gastric acid secretion regardless of the primary stimulus. Results of short term (less than 8 weeks) clinical trials have shown lansoprazole to be significantly superior to placebo and ranitidine in the treatment of duodenal ulcer, both in the rate of healing and in overall healing at 4 weeks. Lansoprazole appears to heal duodenal ulcer more quickly than famotidine, and demonstrates slightly greater efficacy at 4 weeks, although both drugs appear to have equivalent efficacy overall. Gastric ulcers and reflux oesophagitis are also healed by lansoprazole 30 mg/day for 4 to 8 weeks, with healing rates after 8 weeks of approximately 85 to 95% for both indications. Lansoprazole appears to be superior to ranitidine and comparable to omeprazole in treating reflux oesophagitis. Furthermore, lansoprazole has relieved reflux symptoms more quickly than either ranitidine or omeprazole. Preliminary data also indicate that lansoprazole may be effective in the treatment of peptic ulcer disease and reflux oesophagitis refractory to H2-receptor antagonists, and in patients with Zollinger-Ellison syndrome. While direct comparisons with omeprazole are limited, results suggest that lansoprazole, used for short term treatment, is at least as effective as omeprazole in the treatment of peptic ulcer and reflux oesphagitis. Lansoprazole has been well tolerated in short term clinical trials, with an incidence of adverse effects comparable with that of other agents in its therapeutic class. Trials assessing long term tolerability data are ongoing and will be required as part of the assessment of the safety profile, if lansoprazole is to be used prophylactically to prevent ulcer recurrence. Thus, by virtue of its ability to heal ulcers and rapidly relieve associated symptomatology, lansoprazole represents a useful alternative for the treatment of acid related disorders.     

Lansoprazole: pharmacokinetics,pharmacodynamics and clinical uses

Lansoprazole (Prevacid?, TAP Pharmaceuticals, Inc.) is a substituted benzimidazole that inhibits gastric acid secretion. This agent is approved for the short-term treatment of erosive reflux oesophagitis, active gastric ulcer, active duodenal ulcer and the treatment of non-steroidal anti-inflammatory drug (NSAID)-induced gastric and duodenal ulcers. It is also approved for the long-term treatment of healed reflux oesophagitis, healed duodenal ulcer, the treatment of hypersecretory conditions such as Zollinger-Ellison syndrome and the eradication of Helicobacter pylori as a component of triple therapy with lansoprazole, clarithromycin and amoxicillin, or dual therapy with lansoprazole and amoxicillin. Its mechanism of action is to selectively inhibit the membrane enzyme H⁺/K⁺ATPase in gastric parietal cells. In clinical trials, lansoprazole is more effective than placebo or histamine (H₂)-receptor antagonists in the treatment of reflux oesophagitis. Lansoprazole administered at a dose of 30 mg daily produced faster relief of symptoms and superior healing rates in patients with gastric or duodenal ulcers or reflux oesophagitis than H₂-receptor antagonists. A daily dose of 30 mg lansoprazole reduced epigastric pain faster than omeprazole 20 mg daily in patients with peptic ulcer disease but healing rates at 4 and 8 weeks were similar with both agents at these dosages. Lansoprazole was more effective than H₂-receptor antagonists in patients with Zollinger-Ellison syndrome and produced similar treatment outcome to omeprazole. Lansoprazole in combination with clarithromycin and amoxicillin produced similar rates of eradication of H. pylori. In clinical trials, lansoprazole is well-tolerated and has a low frequency of side effects similar to that of H₂-receptor antagonists or omeprazole.     

Omeprazole. An updated review of its pharmacology and therapeutic use in acid-related disorders.

Omeprazole is the first of a new class of drugs, the acid pump inhibitors, which control gastric acid secretion at the final stage of the acid secretory pathway and thus reduce basal and stimulated acid secretion irrespective of the stimulus. In patients with duodenal or gastric ulcers, omeprazole as a single 20 mg daily dose provides more rapid and complete healing compared with ranitidine 150 mg twice daily or 300 mg at nighttime, or cimetidine 800 or 1000 mg/day. Patients poorly responsive to treatment with histamine H2-receptor antagonists respond well to omeprazole--most ulcers healed within 4 to 8 weeks of omeprazole 40 mg/day therapy. Omeprazole 20 or 40 mg/day has been administered as maintenance therapy for peptic ulcer disease for up to 5.5 years with very few ulcer recurrences. In patients with erosive or ulcerative oesophagitis, omeprazole 20 or 40 mg/day produces healing in about 80% of patients after 4 weeks, and is superior to ranitidine with respect to both healing and symptom relief. Healing rates of greater than 80% are achieved after 8 weeks in patients with severe reflux oesophagitis unresponsive to H2-receptor antagonists. Maintenance therapy with a daily 20 mg dose prevents relapse in about 80% of patients over a 12-month period. Omeprazole is considered to be the best pharmacological option for controlling gastric acid secretion in patients with Zollinger-Ellison syndrome. Daily dosages of 20 to 360 (median 60 to 70 mg successfully reduce basal acid output to target levels (less than 10 mmol/h or less than 5 mmol/h in patients with severe oesophagitis or partial gastrectomy) during treatment for up to 4 years. Omeprazole is well tolerated in short term studies (up to 12 weeks); the reported incidence of serious side effects (about 1%) being similar to that seen in patients treated with an histamine H2-receptor antagonist. The longer term tolerability of omeprazole has been investigated in patients treated for up to 5.5 years. Slight hyperplasia, but no evidence of enterochromaffin-like (ECL) cell dysplasia or neoplasia or ECL cell carcinoids has been reported. ECL cell carcinoids have been observed in rats after life-long treatment with high doses of omeprazole or ranitidine, or in rats with partial corpectomy; the weight of experimental evidence indicates that this is a result of prolonged hypergastrinaemia.(ABSTRACT TRUNCATED AT 400 WORDS)     

Misoprostol: a prostaglandin E1 analogue

The pharmacology, pharmacokinetics, clinical efficacy, contraindications and precautions, adverse effects, dosage, and cost of misoprostol are reviewed. Misoprostol is a synthetic analogue of natural prostaglandin E1. It produces a dose-related inhibition of gastric acid and pepsin secretion and enhances mucosal resistance to injury. Misoprostol is extensively absorbed from the stomach and undergoes rapid de-esterification to its biologically active metabolite, misoprostol acid. The average absorption after an oral dose is 88%; peak plasma concentrations of misoprostol acid are achieved in less than 30 minutes. Clinical trials have demonstrated ulcer healing rates of approximately 60-80% in patients with duodenal ulcers who received misoprostol 800 micrograms daily for four weeks. Misoprostol was generally no more efficacious than conventional therapy with the H2-receptor antagonists cimetidine and ranitidine. The healing rate observed for gastric ulcers was less than that observed for duodenal ulcers. In trials involving healthy volunteers and patients with arthritis receiving aspirin, naproxen, tolmetin, ibuprofen, or piroxicam, misoprostol was consistently superior to placebo, cimetidine, and sucralfate in the prevention of nonsteroidal anti-inflammatory drug (NSAID)-induced gastropathy. The majority of these studies have been of short duration; however, long-term studies (up to three months) have corroborated superiority over placebo. Misoprostol is an abortifacient and is contraindicated in pregnant women and women of childbearing potential not using effective contraception. The most common adverse effect of misoprostol therapy is diarrhea, which is often mild and self-limiting and can be minimized by administration of misoprostol after meals and at bedtime. The cost (based on retail price) of four weeks of therapy with misoprostol is comparable to that of other antiulcer agents. Misoprostol has been shown to be an effective agent for the prevention of NSAID-induced gastric ulcers. However, there is no evidence that it offers any clinical advantage over H2-receptor antagonists for the treatment of gastric or duodenal ulcer disease.     

Nizatidine. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and its therapeutic use in peptic ulcer disease

Nizatidine is an H2-receptor antagonist which in animal studies was more active on a weight-for-weight basis than cimetidine in inhibiting basal and stimulated gastric acid secretion. Similarly, studies in humans have confirmed that nizatidine is a potent inhibitor of basal, nocturnal and stimulated gastric acid secretion. As might be expected at this stage of its development, published therapeutic experience with nizatidine is limited. Nevertheless, multicentre therapeutic trials have shown that nizatidine 300mg at bedtime or 150mg twice daily is significantly more effective than placebo for healing active duodenal ulcer, and is apparently as effective as standard doses of ranitidine in increasing the rate of healing of both duodenal and gastric ulcers, and as effective as a standard dose of cimetidine in active duodenal ulcer. When used prophylactically a single 150mg dose of nizatidine at night produces a decrease in the incidence of ulcer recurrence compared with placebo, and a similar rate of decrease to that achieved with ranitidine 150mg. Nizatidine is well tolerated. Unlike cimetidine it does not have any antiandrogenic effects or alter the hepatic metabolism of drugs. However, only wider clinical experience with nizatidine can accurately determine its relative efficacy and tolerability compared with other antiulcer therapy. Thus, early clinical experience suggests that nizatidine is a useful alternative to the histamine H2-receptor antagonists presently in clinical use.     

clinical aspects of Helicobacter pylori eradication therapy in peptic ulcer disease

Background and aims : Although the role of H. pylori in peptic ulcer disease is no longer in dispute, certain aspects of eradication therapy in this condition have yet to be settled. Uncertainties still surround the relationship between Helicobacter pylori status and ulcer healing, the efficacy of eradication therapy in alleviating acute symptoms and healing ulcers, and the prognosis after eradication with respect to recurrence of symptoms, ulcers and complications. The present literature review, encompassing studies published up to October 1995, specifically addresses these issues.
Results : Pooled data show that eradication therapy heals 90% of duodenal ulcers and 85% of gastric ulcers, while individual studies repeatedly confirm that it is more effective at healing ulcers than conventional treatment with anti-secretory drugs. Recent reports indicate that triple therapy regimens for 1 week, provided they include an anti-secretory drug, are sufficient to achieve high rates of healing and rapid symptom relief. A detailed analysis of the data, particularly those from studies reporting healing rates in relation to H. pylori status after eradication therapy, provides strong evidence that eradication of H. pylori produces ulcer healing. Follow-up studies show that ulcer recurrence and complications are rare after eradication treatment in patients with either gastric or duodenal ulcer disease. However, while ulcer symptoms are infrequent during follow-up, a proportion of patients appear to develop gastrooesophageal reflux after eradication.
Conclusions : H. pylori eradication is highly effective in promoting ulcer healing and preventing subsequent ulcer recurrence. These beneficial effects of eradication therapy are observed in patients with either gastric or duodenal ulcers which are associated with H. pylori infection.     

Current concepts in clinical therapeutics: peptic ulcer disease

The epidemiology, pathophysiology, diagnosis, clinical presentation, and treatment of peptic ulcer disease (PUD) are reviewed. PUD occurs commonly, with about 4 million Americans affected in a year. Cigarette smoking, aspirin use, and prolonged corticosteroid use are associated with PUD. The disease's etiology is multifactorial; the long-held assumption that ulcers develop solely because of increased gastric acid secretion is no longer valid. Although duodenal ulcer patients are frequently hypersecretors of acid, gastric ulcer patients more commonly have defective mechanisms for protecting the mucosal lining from acid, pepsin, and other agents. PUD is best diagnosed using an upper gastrointestinal roentgenographic series or using endoscopy. The clinical presentations, which involve epigastric abdominal pain that is relieved by food, milk, or antacids, may aid in diagnosis but are not usually definitive. Treatment is designed to relieve symptoms, heal the ulcer, prevent recurrences, and prevent complications. Of the four currently available drug treatments (cimetidine, ranitidine, antacids, and sucralfate), the treatment of first choice is cimetidine or ranitidine for four or six weeks, respectively, for duodenal and gastric ulcer patients. Antacids should be used as needed for pain, and the patient should be reassessed at the end of this period. For most patients, neither cimetidine nor ranitidine is demonstrably superior to one another. Several agents are under investigation in the U.S., including other H2-receptor antagonists (famotidine and nizatidine), proton-pump inhibitors (omeprazole), prostaglandins (misoprostol, arbasprostil, enprostil, and trimoprostil), antimuscarinic agents (pirenzepine), and tricyclic antidepressants (doxepin and trimipramine). peptic ulcer disease is an important disease. It is best treated with H2-receptor antagonists supplemented with antacids as needed for pain.     

Pharmacological and therapeutic properties of lafutidine (stogar and protecadin), a novel histamine H2 receptor antagonist with gastroprotective activity]

Potent antisecretory agents, such as histamine H2-receptor antagonists and proton pump inhibitors, have achieved great improvement in peptic ulcer therapy. It has, however, been reported that incidence of ulcer relapse is high after discontinuation of these drugs. Insufficient efficacy against NSAID-induced ulcers is also critical. Lafutidine is a novel histamine H2 antagonist with gastroprotective activity. Lafutidine exhibited potent and long-lasting H2 antagonism and prolonged antisecretion. In addition, lafutidine showed a gastroprotective effect against noxious agents-induced gastric mucosal damage through capsaicin-sensitive afferent nerves. Lafutidine showed antiulcer activities against acute ulcer models, prevented gastric ulcer relapse of acetic ulcer, and accelerated the healing of indomethacin-induced antral ulcers in rats. These results suggest the advantage of the combined antisecretory and gastroprotective activities. In clinical studies, lafutidine showed prolonged antisecretion, healing effect against gastric and duodenal ulcers and gastritis, and its potency was equal or superior to that of conventional H2 antagonists. Additionally, lafutidine induced a high transition rate to the E0 stage determined by endoscopical ultrasonography, suggesting the high quality of ulcer healing. Furthermore, effectiveness of lafutidine against NSAIDs-induced ulcer was high. From these results, lafutidine is equal or superior to conventional H2 antagonists in antiulcer potency, and it may be useful for the prevention of ulcer relapse and or treatment of NSAIDs-induced gastroduodenal damage.     

Meta-analysis: the efficacy of intravenous H2-receptor antagonists in bleeding peptic ulcer

BACKGROUND: Although a previous meta-analysis found that intravenous H2-receptor antagonists were only weakly beneficial in bleeding gastric ulcer and of no benefit in bleeding duodenal ulcer, patients with ulcer bleeding continue to receive such treatment. AIM: To re-evaluate the efficacy of intravenous H2-receptor antagonists in ulcer re-bleeding, surgery and mortality by updating the previous meta-analysis. METHODS: After two independent literature searches, randomized, placebo-controlled trials of intravenous H2-receptor antagonists in bleeding ulcer published between 1984 and 2000 were added to those from the initial meta-analysis. Pooled rates of re-bleeding, surgery and death were re-calculated, together with the relative risk reduction, absolute risk reduction, number needed to treat and Mantel-Haenszel odds ratio. RESULTS: Intravenous H2-receptor antagonists did not significantly reduce re-bleeding, surgery or death in bleeding duodenal ulcer. There were small but significant reductions in re-bleeding, surgery and death in bleeding gastric ulcer; the absolute risk reductions were 7.2%, 6.7% and 3.2%, respectively. CONCLUSIONS: Intravenous H2-receptor antagonists are of no value in bleeding duodenal ulcer, although they may be mildly beneficial in bleeding gastric ulcer. Because proton pump inhibitors have a greater inhibitory effect on gastric acid secretion than H2-receptor antagonists, they may be more effective in ulcer bleeding and should be further evaluated for that indication.     

Misoprostol. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in the treatment of peptic ulcer disease

Misoprostol is an analogue of prostaglandin E1 and is the first synthetic prostaglandin analogue to be made available for the treatment of peptic ulcer disease. It inhibits gastric acid secretion in man, and there is also some evidence that it limits the extent of gastrointestinal damage induced by ulcerogenic agents in animals and healthy volunteers at doses lower than those required to inhibit acid secretion. This 'cytoprotective' activity has been explained by several mechanisms, but its contribution to the clinical efficacy of misoprostol in healing established ulcers is doubtful since the drug does not appear to be effective in healing peptic ulcers at non-antisecretory dosages. In clinical trials, ulcer healing has been reported in 60 to 85% of patients with duodenal ulcers and 32 to 54% with gastric ulcers receiving misoprostol 200 micrograms 4 times daily for 4 weeks--the recommended dosage. In comparative studies, the percentage of patients with healed ulcers after misoprostol (800 micrograms daily) was not significantly different from that with cimetidine (1200 mg daily), although there was greater pain relief with cimetidine. No study has yet been published concerning the use of misoprostol as maintenance therapy for the prevention of ulcer recurrence, and no long term tolerability data are available. However, in acute ulcer healing studies (2 to 12 weeks in duration) misoprostol has been well tolerated. Diarrhoea was the most commonly reported symptom, and this was only rarely of sufficient severity to interfere with treatment. No evidence of histopathological changes in the gastric mucosa induced by misoprostol have been reported in man. Evidence of uterine stimulant effects in women receiving misoprostol during the first trimester of pregnancy has resulted in the drug being contraindicated during pregnancy. Thus, misoprostol is a new type of antiulcer drug, providing an alternative approach to the therapy of peptic ulcer disease. It has been shown to be effective and well tolerated in the healing of both gastric and duodenal ulcers. Future studies need to identify the specific types of patients likely to obtain most benefit from treatment, in order to define more clearly the place of misoprostol in the treatment of these indications, as well as addressing the possibility of ulcer prevention with lower doses of misoprostol.     

Lansoprazole: A Comprehensive Review

Lansoprazole is the second member of the substituted benzimidazole class of antisecretory agents approved for use in the United States. These drugs decrease parietal cell acid secretion by inhibiting H⁺,K⁺-adenosine triphosphatase, the final step in the secretion of acid. Lansoprazole has been studied extensively for the short-term treatment of duodenal and gastric ulcers, reflux esophagitis, and Helicobacter pylori-positive peptic ulcer disease; long-term treatment of Zollinger-Ellison syndrome; and maintenance treatment of erosive esophagitis. A dosage of 30 mg/day produced higher healing rates and equivalent or faster relief of ulcer symptoms than ranitidine or famotidine in patients with duodenal or gastric ulcers and reflux esophagitis. Compared with omeprazole 20 mg/day, that dosage provided faster epigastric pain relief in these patients after 1 week, although healing rates for the two agents were equivalent at 4 and 8 weeks. In patients with peptic ulcer refractory to 8-week therapy with histamine₂-receptor antagonists, healing rates were not significantly different between lansoprazole and omeprazole. In patients with Zollinger-Ellison syndrome, lansoprazole was superior to histamine₂-receptor antagonists and was similar in efficacy, safety, and duration of action to omeprazole. Combinations of lansoprazole or omeprazole with one or two antibiotics produced equivalent eradication of H. pylori. In clinical trials, lansoprazole was well tolerated, with frequency of adverse effects similar to that reported with ranitidine, famotidine, and omeprazole.     

Famotidine. An updated review of its pharmacodynamic and pharmacokinetic properties, and therapeutic use in peptic ulcer disease and other allied diseases

Famotidine is a highly selective histamine H2-receptor antagonist. In healthy volunteers and patients with acid hypersecretory disease it is approximately 20 to 50 times more potent at inhibiting gastric acid secretion than cimetidine and 8 times more potent than ranitidine on a weight basis. As shown in placebo-controlled trials, famotidine is effective in healing both duodenal and gastric ulcers. Famotidine 20mg twice daily or 40mg at bedtime achieves healing rates and symptom relief similar or superior to those achieved by cimetidine 800mg daily or ranitidine 300mg daily in patients with peptic ulcer disease. Results of 1 placebo-controlled study suggest that famotidine prevents recurrence of duodenal ulcer, but comparative trials are needed to establish its relative efficacy in maintenance therapy. The few non-comparative trials conducted to date also suggest that famotidine 10 to 20mg twice daily may be effective in the treatment of gastritis and reflux gastro-oesophagitis. In comparative trials, famotidine was similar in efficacy to cimetidine in the treatment of upper gastrointestinal bleeding and to ranitidine in the prevention of pulmonary aspiration of acid. In patients with Zollinger-Ellison syndrome, the potency and long duration of action of famotidine may confer an advantage over other H2-receptor antagonists--in individualised doses (mean 0.33 g/day) famotidine successfully controlled acid secretion for up to 72 months in 1 study of such patients. Accumulated clinical evidence confirms that famotidine is very well tolerated and is free of the antiandrogenic effects infrequently reported with cimetidine. Moreover, famotidine is not associated with altered hepatic metabolism of drugs. Thus, famotidine is an effective, well-tolerated alternative to cimetidine and ranitidine. Famotidine is also promising as maintenance therapy for preventing recurrence of duodenal ulcer and as initial or maintenance treatment of gastric hypersecretory disorders, but further clinical experience, particularly in the long term, is needed to define the relative efficacy and tolerability of famotidine in these indications.