To assess the effect of a restriction on publicly subsidised temazepam 10 mg capsules upon the injection of benzodiazepines by injecting drug users (IDUs).

Cross-sectional study of regular IDUs targeting periods before and after the policy change. Analysis of prescription data, including time-series analysis.

Drug services in the capital cities of New South Wales, Victoria, Tasmania, Queensland and the Northern Territory.

Changes in prescriptions and patterns of benzodiazepine use; harms associated with benzodiazepine use.

There was a decrease in temazepam 10 mg capsule prescriptions and a corresponding increase in temazepam 10 mg tablet prescriptions after the policy change. IDU survey data suggested that IDUs continued to inject benzodiazepines and temazepam capsules. The frequency of the injection of capsules after the restriction appeared similar to that before the policy change. There was no change in the frequency of injection of tablets. Most IDUs reported obtaining their benzodiazepines from doctors, with substantial proportions obtaining capsules even after the restriction. About half the IDUs reported purchasing benzodiazepines on the street. Most IDUs who injected benzodiazepines reported injection-related problems.

Limiting the prescribing of temazepam capsules may have reduced their injection by some IDUs, but additional strategies are needed to reduce the misuse among this group. These may include further restriction of capsule preparations, continued education of doctors and IDUs, and the examination of prescribing practices of individual doctors.