Does prescribing for opiate addiction change after national guidelines? : methadone and buprenorphine prescribing to opiate addicts by general practitioners and hospital doctors in England, 1995-2005

Aim: To assess changes in opiate prescribing (1995-2005) following a decade of national guidelines to address substandard opiate substitution prescribing for heroin addiction. Design: A repeat national survey (1995 and 2005) using random one-in-four samples of all community pharmacies in England, achieving response rates of 75% (1847/2475) in 1995 and 95% (2349/2473) in 2005. Data were obtained on 3732 (1995 data) and 9620 (2005 data) prescriptions dispensed in the preceding month from the 936 and 1463 pharmacies who were currently dispensing. Measurements: We have measured impact on practice for seven specific recommended changes. Findings: Between 1995 and 2005 the number of substitute opiate prescriptions doubled (x2.03). By 2005, methadone still dominated (down from 97% to 83%), buprenorphine increased (from 1% to 16%) and other opiate medications virtually disappeared. Changes in the direction of national guidelines included: increased daily dose of methadone (from 47.3 mg to 56.3 mg), more frequent dispensing (from 38% to 60% as daily instalments), more supervised consumption (from 0% to 36%) and fewer methadone tablets (from 10.9% to 1.8%). Nevertheless, despite the increased mean daily dose, only 41.0% of prescriptions for methadone were for daily doses in the recommended 60-120 mg dose range. Only one change was not in the direction of the national guidelines - the proportion of prescriptions from GPs fell from 41% to 30%, although this still represented an approximate 50% increase in the extent of GP prescribing. Conclusion: Doubling in provision of opiate substitute treatment has occurred, alongside significant improvements in the nature of this treatment. These positive changes have occurred in the direction of six out of seven of the UK national guidelines.