Gastric safety and entericcoated aspirin

Abstract

Kelly and colleagues1Kelly JP Kaufman DW Jurgelon JM Sheehan J Koff RS Shapiro S Risk of aspirin-associated major upper gastrointestinal bleeding with enteric coated or buffered product.Lancet. 1996; 348: 1413-1416Summary Full Text Full Text PDF PubMed Scopus (400) Google Scholar report that low doses of enteric-coated or buffered aspirin can promote upper gastrointestinal bleeding to the same extent as plain aspirin. Although gastric damage by aspirin is not prevented by buffering, the comparative safety of enteric-coated preparations has been controversial because of endoscopic studies reporting fewer gastric erosions and less bleeding than with regular aspirin. The enteric-coated drug may be less harmful to the stomach during very short-term administration since there may be little or no contact with the gastric mucosa, but untoward gastric effects are likely after repeated administration.2Jaszewski R Frequency of gastroduodenal lesions in asymptomatic patients on chronic aspirin or nonsteroidal antiinflammatory drug therapy.J Clin Gastroenterol. 1990; 12: 10-12Crossref PubMed Scopus (44) Google Scholar, 3Savon JJ Allen ML di Marino AJ Hermann GA Krum RP Gastrointestinal blood loss with low dose (350 mg) plain and enteric-coated aspirin administration.Am J Gastroenterol. 1995; 90: 581-585PubMed Google Scholar, 4Guslandi M Gastric toxicity of anti-platelet therapy with low-dose aspirin.Drugs. 1997; 53: 1-5Crossref PubMed Scopus (30) Google Scholar Aspirin is thought to injure the gastric mucosa through local and systemic effects, the latter being due to inhibition of gastric cycloxygenase (with blockade of gastric prostaglandin production) after the drug is absorbed, irrespective of route of administration or formulation given.4Guslandi M Gastric toxicity of anti-platelet therapy with low-dose aspirin.Drugs. 1997; 53: 1-5Crossref PubMed Scopus (30) Google Scholar Prophylaxis against aspirin associated gastroduodenal damage, even when enteric-coated preparations are used, is necessary. H2-receptor antagonists can prevent duodenal (but not gastric) lesions by non-steroidal anti-inflammatory drugs, but specific data concerning aspirin are not available. By contrast, co-prescription of misoprostol can protect both stomach and duodenum from the harmful effects of NSAIDs. The protective effect of misoprostol against low-dose aspirin has been described by UK investigators: 100 μg daily misoprostol was better than placebo in preventing gastric haemorrhagic lesions induced by a 4-week course with aspirin 300 mg daily.5Goddard AF Donnelly MT Filipowicz B Morant SV Shield MJ Hawkey CJ Low dose misoprostol as prophylaxis against low dose aspirin-induced gastroduodenal mucosal injury.Gut. 1996; 39: A33Google Scholar These data suggest that high-risk patients with strong indications for antiplatelet treatment with low-dose aspirin may benefit from prophylactic intake of a very low dose of the prostaglandin analogue.