title: The risk of acute pancreatitis associated with acid-suppressing drugs.
abstract: OBJECTIVE
  To assess the risk of acute pancreatitis associated with use of acid-suppressing drugs.
  
  
  METHODS
  We conducted a retrospective cohort study with a nested case-control design within the General Practice Research Database (GPRD) in the United Kingdom. The cohort included 180 178 persons aged 20-74 years, who had received at least one prescription of cimetidine, famotidine, nizatidine, ranitidine, lansoprazole, or omeprazole from January 1992 to September 1997 and who did not have major risk factors for pancreatic diseases. Patients with a computerized medical history compatible with idiopathic acute pancreatitis were validated through review of medical records. For the nested case-control analysis 1000 controls were randomly selected from the study population.
  
  
  RESULTS
  We identified 88 potential cases of idiopathic acute pancreatitis. Medical records were available for 86. After review of these records 36 cases of acute pancreatitis were confirmed. Seven cases occurred during nonuse, corresponding to a background incidence rate (IR) of 4.4/100 000 person-years (PY). Six cases occurred during current use of ranitidine (IR 10.5/100 000 PY), five patients were current users of cimetidine (IR 13.9/100 000 PY), and three were current users of omeprazole (IR 7.8/100 000 PY). There were no cases among current users of famotidine, lansoprazole, or nizatidine. Relative risk (RR) compared with nonuse and corrected for age, gender, calendar year and use of medication known to be associated with acute pancreatitis was 1.3 (95% CI: 0.4,4.1) for ranitidine, 2.1 (95% CI: 0.6,7.2) for cimetidine, and 1.1 (95% CI: 0.3,4.6) for omeprazole.
  
  
  CONCLUSIONS
  The results of this study do not support an association between acute pancreatitis and the use of acid-suppressing drugs, although a substantial increase in risk cannot be excluded with confidence.
authors.affiliation: Pharmaco-epidemiology Unit, Departments of Internal Medicine and Epidemiology & Biostatistics, Erasmus University Medical School, Rotterdam, The Netherlands. eland@inw2.azr.nl
authors.forename: I A
authors.initials: IA
authors.lastname: Eland
authors.forename: C H
authors.initials: CH
authors.lastname: Alvarez
authors.forename: B H
authors.initials: BH
authors.lastname: Stricker
authors.forename: L A
authors.initials: LA
authors.lastname: Rodríguez
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000863:Antacids / Q000009:adverse effects*; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000139:chemically induced*; D012189:Retrospective Studies; D012306:Risk
chemical_list: D000863:Antacids