Prescriptions for antiulcer drugs in Australia: volume, trends, and costs
BMJ 2001; 323 doi: https://doi.org/10.1136/bmj.323.7325.1338 (Published 08 December 2001) Cite this as: BMJ 2001;323:1338
- Johanna I Westbrook, associate professor, medical informatics (J.Westbrook{at}unsw.edu.au)a,
- Anne E Duggan, staff specialistb,
- Jean H McIntosh, research assistantc
- a Centre for Health Informatics, University of New South Wales, Kensington 2052, NSW, Australia
- b Department of Gastroenterology, John Hunter Hospital, New Lambton Heights 2305, NSW, Australia
- c School of Health Information Management, University of Sydney, Lidcombe 1825, NSW, Australia
- Correspondence to: J I Westbrook
- Accepted 29 August 2001
H2 receptor antagonists and proton pump inhibitors have markedly changed the management of peptic ulcer and gastro-oesophageal reflux disease; they have also changed the profile of national drug budgets. Antiulcer drugs have retained the leading position in drug sales worldwide: sales of antiulcer drugs were valued at $US12.9 billion (£8.6bn) in 1998 and were increasing at 3% a year.1
Since 1992 the Australian government's pharmaceutical benefits scheme has required prescribers of proton pump inhibitors to certify the presence of peptic ulcer disease or ulcerating oesophagitis (confirmed by endoscopy, radiography, or surgery) and refractory to treatment with other drugs, scleroderma oesophagus, or Zollinger-Ellison syndrome. The aim of this study was to assess how these restrictions have affected prescribing of antiulcer drugs.
Participants, methods, and results
We analysed data from the pharmaceutical benefits scheme on the number of prescriptions for H2 receptor antagonists, proton pump inhibitors, and cytoprotectant agents for the financial years 1992–3 to 1996–7 and 1999. Data on misoprostol and treatments to eradicate Helicobacter pylori were available only for 1999.
In 1999 antiulcer drugs made up 6.1% of all prescriptions dispensed. They were the second most costly group of drugs to the government, consuming 11.1% of the total pharmaceutical benefits scheme budget (table). Ranitidine, famotidine, nizatidine, omeprazole, and lansoprazole were all among the 100 drugs most often prescribed, and, with pantoprazole, were among the 100 most costly drugs to the government. Ranitidine was the third most commonly prescribed, and omeprazole was the second most costly. The total number of prescriptions for proton pump inhibitors was only half (51%) that for the H2 receptor antagonists, but proton pump inhibitors were 2.4 times more costly. H pylori eradication treatments made up only 1.3% of all prescriptions for antiulcer drugs.
Prescriptions for antiulcer drugs in Australia, 1999. Number, cost, and ranking for frequency and cost to the government pharmaceutical benefits scheme
Between 1992–3 and 1999 total prescriptions for H2 receptor antagonists, proton pump inhibitors, and cytoprotectant agents increased by 109%—increases of 51% for H2 receptor antagonists and 1228% for proton pump inhibitors and a decrease of 84% for cytoprotectants. Prescriptions for proton pump inhibitors increased by 40% between 1995–6 and 1996–7 and by 43% between 1996–7 and 1999. Prescriptions for H2 receptor antagonists increased by 3% between 1995–6 and 1996–7 and decreased by 4% between 1996–7 and 1999. Proton pump inhibitors have continued to make up an increasing proportion of total antiulcer drugs prescribed (13% in 1994-5, 20% in 1995-6, 25% in 1996-7, and 34% in 1999).
Comment
The proportion of proton pump inhibitors prescribed relative to H2 receptor antagonists is at odds with the guidelines for the Australian pharmaceutical benefits scheme and with data on the epidemiology of refractory oesophagitis. Despite restrictions, proton pump inhibitors accounted for 34% of prescriptions for antiulcer drugs and for 51% of government expenditure on antiulcer drugs in 1999. Around 7-8% of consultations with general practitioners are for gastrointestinal problems, and this proportion did not change between 1992 and 1999.2 Australians seem to consult at higher rates for gastrointestinal symptoms than do other nationalities.3 The continued rise in the number of prescriptions for proton pump inhibitors, combined with evidence of inappropriate use,4 suggests that the restrictions have had a limited impact on prescribing behaviour.
In contrast, despite the well established benefits of eradication of H pylori in the management of peptic ulcer disease, only 1.3% of total prescriptions in 1999 were for treatments to eradicate H pylori.
The decline in the number of prescriptions for H2 receptor antagonists is consistent with experience in the United States and Britain. The National Institute for Clinical Excellence has issued guidelines that are expected to reduce prescriptions for proton pump inhibitors by 15% in England and Wales.5 The Australian experience provides some much needed comparative data for future evaluations of the impact of these guidelines.
Acknowledgments
Contributors: JIW designed the study, undertook analyses, and participated in writing the paper. AED participated in analysis and had a substantial role in writing the paper. JHM extracted drug data, assisted in analysis, and was involved in writing the paper. JIW and AED are joint guarantors of the paper.
Footnotes
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Funding None.
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Competing interests None declared.