Br J Clin Pharmacol. 2000;50:35-42.

The incidence of adverse events and risk factors for upper gastrointestinal disorders associated with meloxicam use amongst 19 087 patients in general practice in England: cohort study



1Richard M. Martin, 1Pipasha Biswas and 2Ronald D. Mann

1Drug Safety Research Unit, Bursledon Hall, Blundell Lane Southampton, SO31 1AA, UK
2School of Medicine, Faculty of Medicine, Health and Biological Sciences, University of Southampton,  Southampton, UK

Abstract

Aims Meloxicam is a novel nonsteroidal anti-inflammatory drug (NSAID) which may be associated with fewer adverse upper gastrointestinal events than other NSAIDs because it preferentially inhibits the inducible enzyme cyclo-oxygenase-2 relative to the constitutive isoform, cyclo-oxygenase-1.  The aims of the study were to: determine the rate of adverse events associated with meloxicam in general practice, stratify these rates by selected risk factors, and to identify signals of previously unsuspected adverse events associated with meloxicam.

Methods As part of the national prescription-event monitoring pharmacovigilance system for newly launched drugs in general practice, all patients prescribed meloxicam in England between December 1996 and March 1997 were identified by the central Prescription Pricing Authority.  We sent short questionnaires to all prescribers asking about adverse events experienced within 6 months of the last prescription.

Results There were 19,087 patients in the study. The rate of dyspepsia during the last month of exposure was 28.3 per 1,000 patient-months.  There were 33 reports of upper gastrointestinal haemorrhage during treatment (rate: 0.4 per 1,000 months).  A history of gastrointestinal disorder in the previous year was associated with an increased rate of dyspepsia (rate ratio: 3.0; 95% confidence interval: 2.6, 3.4), abdominal pain (2.1; 1.6, 2.6), and peptic ulcer (4.0; 1.4, 13.2).  Prior NSAID use was associated with a 20-30% decrease in the rate of dyspepsia and abdominal pain in patients starting meloxicam, while patients prescribed concomitant gastroprotective agents had a two to three-fold increased rate of dyspepsia, abdominal pain and peptic ulceration.  Other rare events were thrombocytopenia (n=2); interstitial nephritis (n=1) and idiosyncratic liver abnormalities (n=1).

Conclusions In the absence of gastro-intestinal risk factors the incidence of gastrointestinal disturbance was low.  Such risk factors should be carefully reviewed prior to prescribing meloxicam.

KEY WORDS -
adverse drug reaction,  cardiotoxicity,  drug monitoring,  gastrointestinal toxicity,
liver toxicity,  meloxicam,  nephrotoxicity,  nonsteroidal anti-inflammatory agent,
pharmacoepidemiology,  prescription-event monitoring