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Effect of national guidelines on prescription of methadone: analysis of NHS prescription data, England 1990-2001

BMJ 2003; 327 doi: https://doi.org/10.1136/bmj.327.7410.321 (Published 07 August 2003) Cite this as: BMJ 2003;327:321
  1. John Strang, professor of the addictions1 (j.strang{at}iop.kcl.ac.uk),
  2. Janie Sheridan, research worker in the addictions1
  1. 1National Addiction Centre (Maudsley/Institute of Psychiatry), London SE5 8AF
  1. Correspondence to: J Strang
  • Accepted 23 May 2003

Introduction

Though there is strong evidence to support the use of methadone maintenance for opiate addiction1 it is often delivered poorly. Evidence based guidelines were developed in 1996 and 1999 (see www.doh.gov.uk/drugdep.htm and further details on bmj.com) and widely publicised in the United Kingdom.2 3 In 1998 we found scant evidence of any impact4 and concluded that “if planners are awaiting major change in methadone prescribing as a result of central exhortation, they should not hold their breath.” However, perhaps guidelines may have a slower cumulative effect.

Method and results

We examined data on all NHS methadone prescriptions dispensed by community pharmacists in England. These account for 98% of methadone prescriptions in England.5 Unpublished commercial data indicate that 95% of methadone prescriptions from general practitioners are for addiction treatment (IMS Health).

To investigate the impact of the guidelines we used two specific recommendations from the Department of Health (the 1996 taskforce report and the Orange Guidelines 1999): firstly, that prescribing of methadone in tablet form should cease (based on concerns about intravenous misuse), and, secondly, that injectable methadone (methadone ampoules) should not be prescribed as mainstream treatment. We examined the proportion of methadone prescriptions per year issued as oral syrup, tablets, or injectable ampoules to identify any change of professional practice.

We examined the six years preceding 1996 (1990-5) to establish prevailing trends in methadone prescribing and then the six years during which the new guidelines were introduced (1996-2001) to study any change. Between 1990 and 2001, NHS prescriptions for methadone dispensed in England tripled—from 425 400 to 1 318 100 annually—increasing every year. However, the proportionate annual increase fell from 15.3%, 23.8%, and 21.1% (first three years) down to increases of 2.7%, 3.6%, and 3.8% (last three years) (table).

Total annual number of NHS methadone prescriptions in England (total and by type), 1990-2001

View this table:

Over the six year baseline period (1990-5), the proportion of methadone prescriptions prescribed as tablets was steady at between 7.8% and 9.8% annually. Thereafter, the proportion steadily reduced (1% per annum) to 4.0% by 2001, and the absolute number also fell every year. Similarly, prescriptions for injectable methadone were stable for 1990-5 (range 8.0% to 9.7%, peaking at 9.7% in 1994) but steadily reduced thereafter, from 8.7% in 1995 to 3.9% in 2001. From 1997 the absolute number of prescriptions as ampoules fell annually.

Comment

Over the past decade, the extent of methadone prescribing in England has tripled, deriving from a substantial year on year increase that was greatest during the first half of the 1990s. Every year community pharmacies across England dispense over 1.25 million NHS prescriptions for methadone, suggesting that about 50 000 opiate addicts are receiving methadone at any one time.

Since 1996 there has been a profound change in national practice regarding methadone prescribing in the directions proposed by the new national recommendations.2 3 Over six years (1996 compared with 2001) the proportions prescribed as tablets (from 9.8% to 4.0%) and as injectable ampoules (from 8.7% to 3.9%) have halved, contrasting with the predominantly steady state of the preceding six year period.

Our data constitute objective evidence that the widespread publishing of national guidelines was followed by major change in national patterns of prescribing, with change occurring gradually and, at least in this instance, still accumulating after six years. We conclude that the eventual impact of national guidance will be substantial; change is not immediate and may take several years; and researchers and planners should not make premature judgment.4

Embedded ImageSeebmj.comfor details of the national guidance

The aggregated raw data on NHS prescriptions for methadone dispensed by community pharmacists were provided by the Statistics Division 1E, Department of Health, England. We thanks IMS Health for providing data on the proportion of methadone prescriptions prescribed as addiction treatment.

Footnotes

  • Contributors JS conceived the idea for the examination. Data were obtained by both JS and JSh. JS undertook the data scrutiny and prepared the first draft of the manuscript. Both JS and JSh worked on the final version. JS is the guarantor.

  • Funding None.

  • Conflict of interest Both authors contributed to the 1996 Task Force report and were members of the working group (chaired by JS) that prepared the 1999 Department of Health's Drug Misuse and Dependence: Guidelines on Clinical Management (Orange Guidelines).

References

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