Treatment of NSAID-induced gastrointestinal lesions with cimetidine: an international multicentre collaborative study

Management of NSAID-induced gastrointestinal toxicity: focus on proton pump inhibitors

The association between NSAIDs and the presence of upper gastrointestinal (GI) complications is well established. Evidence that acid aggravates NSAID-induced injury provides a rationale for minimizing such damage by acid suppression. Proton pump inhibitors (PPIs) appear to be very effective in treating NSAID-related dyspepsia, and also in healing gastric and duodenal ulcers in patients continuing to receive the NSAID. An analysis of data from comparative studies of PPIs versus ranitidine, misoprostol and sucralfate shows a therapeutic advantage in favour of the PPI. Several studies now confirm the efficacy of co-therapy with PPIs in the short- and long-term prevention of NSAID-induced upper GI injury. PPIs are more effective than histamine H(2)-receptor antagonists at standard dosages in reducing the risk of gastric and duodenal ulcer, and are superior to misoprostol in preventing duodenal but not gastric lesions. However, when balancing effectiveness and tolerance, PPIs may be considered the treatment of choice in the short- and long-term prevention of NSAID-related mucosal lesions. To date, there are only a few published articles dealing with the role of PPIs in the prevention of upper GI complications. Recent epidemiological and interventional studies provide some evidence that PPIs are of benefit. However, more controlled studies using clinical outcomes are needed to establish the best management strategy (PPIs combined with traditional NSAIDs or with cyclo-oxygenase-2 selective inhibitors) especially in patients with multiple risk factors, in patients using concomitant low-dose aspirin, corticosteroids or anticoagulants (high risk group), or in patients with a history of ulcer complications (very high risk group). Furthermore, it should be underlined that Helicobacter pylori infection positively interacts with the gastroprotective effect of PPIs; therefore, the true efficacy of these drugs in preventing NSAID-related ulcer complications should be reassessed without the confounding influence of this microorganism.

Is ranitidine therapy sufficient for healing peptic ulcers associated with non-steroidal anti-inflammatory drug use?

Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) increases the risk of serious gastroduodenal events. To minimise these risks, patients often require concomitant acid-suppressive therapy. We conducted a literature review of clinical trials examining use of ranitidine 150 mg twice daily to heal gastroduodenal ulcers (GU) in NSAID recipients. Seven studies were identified. After 8 weeks' treatment with ranitidine, GU healing rates ranged from 50% to 74% and rates of duodenal ulcer (DU) healing ranged from 81% to 84%. Ranitidine was more effective when NSAIDs were discontinued (healing rates reaching 95% and 100%, respectively). The ulcer healing rate with sucralfate was similar to that of ranitidine. However, proton pump inhibitor (PPI) therapy was associated with significantly greater rates of both GU and DU healing than ranitidine; 8-week GU rates were 92% and 88% with esomeprazole 40 mg and 20 mg, respectively (vs. 74% with ranitidine, p < 0.01). For omeprazole, 8-week healing rates were 87% with omeprazole 40 mg and 84% with omeprazole 20 mg (vs. 64% for ranitidine, p < 0.001), and for lansoprazole the corresponding values were 73-74% and 66-69% for the 30 mg and 15 mg doses, respectively (vs. 50-53% for ranitidine, p < 0.05). In the PPI study reporting DU healing the values were 92% for omeprazole 20 mg (vs. 81% for ranitidine, p < 0.05) and 88% for omeprazole 40 mg (p = 0.17 vs. ranitidine). NSAID-associated GU are more likely to heal when patients receive concomitant treatment with a PPI rather than ranitidine.

Modulation of NSAID-induced antinociceptive and anti-inflammatory effects by α2-adrenoceptor agonists with gastroprotective effects

Tizanidine, an alpha2-adrenergic receptor agonist with myospasmolytic action, is indicated for the treatment of back pain either as monotherapy or in combination with nonsteridal anti-inflammatory drugs (NSAIDs). Tizanidine (0.25-1.0 mg/kg) significantly produced analgesic and anti-inflammatory effect in acetic acid induced writhing in mice and carrageenan-induced paw edema in rats, respectively. The effects were comparable with clonidine (0.25 and 0.50 mg/kg), another alpha2-agonist. Yohimbine (1 mg/kg), alpha2-adrenergic antagonist reversed the effect of tizanidine. Tizanidine (0.25 mg/kg) and clonidine (0.25 mg/kg) significantly potentiated the antinociceptive and anti-inflammatory effect of NSAIDs (nimesulide, meloxicam and naproxen). Tizanidine (1 mg/kg) did not alter basal pH, acidity (free and total) of gastric content and did not produce any mucosal injury in fasted rats. Tizanidine (1 mg/kg) significantly reduced meloxicam (UD50 3.21 mg/kg), nimesulide (UD50 24.52 mg/kg) and naproxen (UD50 14.10 mg/kg)-induced ulcerogenic effect (ulcer index, pH and free/total acidity). It is expected that tizanidine exerted gastrotprotection through stimulation of gastric and central alpha2-adrenergic receptors. Present investigation suggested that tizanidine not only enhance the analgesic and anti-inflammatory effect of NSAIDs but also improved gatstrointestinal tolerability of NSAIDs through modulation of central alpha-2-receptors. From this study, it can be speculated that tizanidine and NSAID combination therapy would prove to be a novel approach to treat nociceptive/inflammatory conditions with improved gastric tolerability of NSAIDs.

Prophylaxis and treatment of non-steroidal anti-inflammatory drug-induced upper gastrointestinal side-effects

The use of specific agents to heal mucosal lesions or to prevent non-steroidal anti-inflammatory drug toxicity, has focused upon two approaches: replacement of prostaglandin deficiency and inhibition of acid secretion. Acid suppression with traditional ulcer healing doses of H2-blockers is effective in healing gastric and duodenal ulcers upon discontinuation of the offending drug. In the event the non-steroidal anti-inflammatory drug must be continued, the use of H2-blockers is associated with a decrease in the healing rate. In long-term prevention studies, H2-blockers significantly reduce duodenal ulcer rates, but are ineffective in reducing gastric ulceration. More potent acid inhibition with a double-dose of H2-blockers (famotidine 80 mg daily, ranitidine 600 mg daily) may reduce the risk of gastric and duodenal ulcers. Marked acid suppression with proton pump inhibitors (omeprazole 20-40 mg, lansoprazole 30 mg daily) also appears to be very effective in healing gastric and duodenal ulcers in patients continuing the offending drug as well. An analysis of pooled data from comparative studies on omeprazole vs ranitidine, misoprostol and sucralfate shows a therapeutic advantage in favour of the proton pump inhibitor, ranging from 10 to 40%. In long-term prevention studies, omeprazole (20 mg daily) and pantoprazole (40 mg daily) have also been shown to reduce the risk of gastric and duodenal ulcers and non-steroidal anti-inflammatory drug-related dyspepsia. Current data from recent comparative studies of omeprazole (20 mg daily) vs ranitidine (150 mg daily) and misoprostol (200 microg daily) showed that, after 6 months' follow-up, the proton pump inhibitor was significantly superior to control drugs in reducing the risk both of gastric and duodenal ulcer. Misoprostol (at doses ranging from 400 microg to 800 microg/day) is an effective form of therapy for preventing non-steroidal anti-inflammatory drug-induced gastroduodenal lesions. However high-dose misoprostol only, seems adequate for the prevention of ulcer complications, mainly in high-risk non-steroidal anti-inflammatory drug users. Thus, available data are undoubtedly in favour of the proton pump inhibitors as well tolerated and effective drugs in the prophylaxis and treatment of non-steroidal anti-inflammatory drug-related mucosal lesions in the gastrointestinal tract.

Nonsteroidal anti-inflammatory drug gastrointestinal toxicity

Nonsteroidal anti-inflammatory drugs (NSAIDs) are currently the most widely used class of therapeutic agents. By inhibiting cyclooxygenase (COX) and reducing gastrointestinal prostaglandins, they provide effective analgesia and suppress inflammation in a variety of conditions. However, through the same mechanism of COX inhibition, they also cause significant gastrointestinal toxicity. One of the most common methods to reduce NSAID-induced gastrointestinal toxicity has been to co-prescribe prophylactic therapies such as acid-reducing agents or the synthetic prostaglandin analogue, misoprostol. More recently safer NSAIDs, such as the COX-2 specific NSAIDs or the nitric oxide-releasing NSAIDs, have been developed or are currently in development. This article reviews mechanisms of NSAID-induced gastrointestinal toxicity. Also reviewed are data on the gastrointestinal consequences of the prophylatic co-therapies, COX-2 specific NSAIDs and nitric oxide-releasing NSAIDs.

Arthrotec: the evidence speaks for itself

This article examines the most recently published scientific literature on arthritis therapy options and available mucosal-protective agents. Emphasis is placed on the risks of current nonsteroidal anti-inflammatory drug (NSAID) therapy, the options for reducing such risks, and the published information that either supports or refutes current thinking in these areas. A comprehensive evaluation is made of clinical data related to the use of Arthrotec (diclofenac/misoprostol) in the treatment of arthritis. A recent meta-analysis of the prophylaxis of NSAID-associated upper gastrointestinal complications is reviewed. The results of this meta-analysis should help to consolidate much of the current scientific literature on the safe and effective treatment of arthritis.

Nizatidine in therapy and prevention of non-steroidal anti-inflammatory drug-induced gastroduodenal ulcer in rheumatic patients

Two hundred and sixty-nine patients with various rheumatic disorders who had been treated with non-steroidal anti-inflammatory drugs (NSAID) for at least 3 weeks were enrolled in this randomized double-blind multicentre trial. Entry criteria were the presence of an ulcer in the gastric and/or duodenal mucosa (> 3 mm and < 20 mm in diameter) and dyspeptic symptoms. The patients were treated with 150 mg nizatidine nocte (n = 86), 2 x 150 mg/d (n = 93) and 2 x 300 mg/d (n = 90) nizatidine. All patients continued to take their original NSAID medication. The three nizatidine groups were well matched with respect to important patient characteristics. After 8 weeks of treatment more than 90% of gastric and duodenal ulcers (DU) had healed under all three nizatidine dosages. There was a tendency to higher healing rates in the case of gastric ulcers after 4 weeks following the higher dose of nizatidine. Erosion, in the stomach and duodenum as well as oesophagitis, improved to a similar degree with all nizatidine doses. There were similar improvements in clinical symptoms such as epigastric pain, heartburn etc. Consumption of additional antacids were similar in all three groups. In the subsequent prevention trial, 237/221 patients were followed for 3/6 months. In addition to their continued antirheumatic medication 116/107 received nizatidine 150 mg nocte and 121/114 patients 2 x 150 mg nizatidine daily. The cumulative relapse rates within 6 months averaged 5.5% in the low and 1.8% in the high dose group (NS). The safety of nizatidine was assessed as good in both the therapeutic and the preventive trial.(ABSTRACT TRUNCATED AT 250 WORDS)

Review article: non-steroidal, anti-inflammatory drugs--the extending scope of gastrointestinal side effects

The gastrointestinal side effects of non-steroidal, anti-inflammatory drugs extend beyond the duodenal bulb, and comprise a variety of lesions in all parts of the gut. Gastroduodenal ulceration is quantitatively dominant, although a major part of these lesions probably go unnoticed and heal spontaneously. Adaptation has been demonstrated for acetylsalicylic acid, and may be of importance for other substances as well. Non-steroidal anti-inflammatory drugs (NSAIDs) may induce relapse of inflammatory bowel disease. Permeability changes and mucosal inflammation are found in the small and large bowel in the majority of subjects taking NSAIDs, although the clinical significance is still not clear. Ulceration and perforation do, however, occur in this part of the gut as well. Treatment of NSAID-associated ulceration is similar to traditional ulcer treatment, possibly with extended treatment duration if the NSAID is continued. Prophylaxis is of some value, but is not required for every patient receiving an NSAID.

Sucralfate for prevention of naproxen-induced mucosal lesions in the proximal and distal gastrointestinal tract

To study the protective effect of Sucralfate on Naproxen-induced mucosal lesions, 16 healthy, male volunteers were given Naproxen 500 mg b.i.d. together with Sucralfate 2 g b.i.d. or placebo in a double-blind, crossover study. Drug periods were 1 week, with a 3-week wash out in between. Mucosal lesions in stomach and duodenum were assessed by upper endoscopy before and after each drug period, using a visual analogue with separate scoring of mid- and distal duodenal lesions. 51Cr-EDTA absorption tests were performed to demonstrate possible changes in distal gut permeability. In addition, subjective symptoms were registered. Both drug periods induced significant lesions in the stomach and duodenum. Statistically speaking, fewer changes were found in the stomach and duodenal bulb after Sucralfate co-administration, whereas no significant reduction of lesions was seen in the distal duodenum. The 51Cr-EDTA absorption was increased in both periods, indicating deleterious effects to distal parts of the gut, but our results did not demonstrate Sucralfate-mediated protection from these changes. Symptoms were modest, and equal in the two periods. We conclude that Sucralfate may offer protection in the gastric and proximal duodenal mucosa, but no such protective effect was seen distally to the duodenal bulb.

Cimetidine tablets or suspension for the prevention of gastrointestinal mucosal lesions caused by non-steroidal, anti-inflammatory drugs

We compared the protection offered by cimetidine 400 mg b.i.d. as tablets or suspension vs. placebo, in Naproxen-induced gastrointestinal damage in 17 healthy males. Upper endoscopy was performed before and after each drug period, with separate evaluation of duodenal mucosa distal to the duodenal bulb. 51Cr-EDTA absorption tests were done to assess distal mucosal integrity, and symptoms were registered. All regimens caused a significant increase in mucosal damage (p less than 0.01). Cimetidine tablets gave a significantly lower damage score than placebo for gastritis/duodenitis and hemorrhagic lesions in the stomach/duodenal bulb, and for the sum of scores in both scoring regions (p = 0.02). Cimetidine suspension was not significantly different from placebo for any of the endoscopic parameters. The 51Cr-EDTA absorption was significantly increased after all drug periods. However, there was no difference between the three drug combinations. Symptoms reported were mild and equal in the three groups. Cimetidine tablets offered protection against Naproxen-induced mucosal damage, primarily in the stomach and duodenal bulb, but lacked any effect on permeability changes. Cimetidine suspension was not significantly different from placebo in any respect.