RESUMEN
INTRODUCTION AND AIMS: To investigate the prevalence and nature of injecting behaviour among patients on Methadone Maintenance Treatment (MMT) programs. DESIGN AND METHODS: A self-reported questionnaire was handed to 423 patients enrolled in MMT across six clinics in the lower North Island of New Zealand. RESULTS: A total of 151 patients responded, giving a 35.6% response rate. One hundred and twenty (79.5%) respondents reported they had injected methadone while enrolled in MMT, 84 (55.6%) had injected methadone in the last year and of those 43 (35.8%) had injected methadone in the last week. Reasons given for injecting of methadone included: rapid onset of effect, needle fixation and euphoria. Time on the methadone programme was negatively associated with ever injecting methadone [odds ratio (95% CI) 0.92 (0.85-0.99), P = 0.029] and injecting other substances [odds ratio (95% CI) 0.93(0.87-1.0), P = 0.046]. More frequent pharmacy-observed consumption was associated with increased injecting of other substances [odds ratio (95% CI) 1.32 (1.09-1.59), P = 0.005] but not methadone. The time a person had been enrolled on the methadone programme was associated with decreased use of other substances [odds ratio (95% CI) 0.93 (0.87-1.0), P = 0.046]. DISCUSSION AND CONCLUSIONS: Many individuals on MMT continue to inject their methadone. In this sample, the frequency of injection of methadone did not correlate with prescribed dose or takeaway arrangements. The beneficial impact of time on the programme emphasises the importance of retention in treatment. It is suggested that these results also indicate a need for routine education concerning safe injecting.