Prospective cohort to assess the impact of removing non-prescription codeine in Australia

Background and Aims

International awareness of problems associated with over-the-counter (OTC) pharmaceuticals containing codeine is growing and regulatory responses have predominantly focused on restricting access and improving guidelines for supply of low-dose codeine preparations. In February 2018, Australia moved codeine from OTC to prescription-only medication. We aimed to evaluate the impact of the rescheduling in a prospective cohort of people frequently consuming OTC codeine.

Design, Setting and Participants

An online prospective longitudinal study of 259 Australian adults consuming OTC codeine at least multiple times per week over the previous six months. Survey points were 3 months prior to the policy change; and 1, 4, and 12 months following.

Measurements

Pain and activity level were evaluated using the Pain Intensity, Enjoyment of Life and General Activity Assessment Tool and the Pain Self-Efficacy Questionnaire. Mental health was evaluated using the Patient Health Questionnaire – 9 and the Patient Health Questionnaire – GAD. Risk of codeine dependence was evaluated using the Severity of Dependence Scale and the Alcohol Use Disorder and Associated Disabilities Interview Schedule-5. Information on medication use was also collected.

Findings

Initial analyses indicated that after the policy change, participants’ average number of visits to see their general practitioner for prescription codeine in the past three months increased by 60%. Importantly, the proportion of participants screening positive for likely codeine dependence had also reduced (30% at baseline, 21% 6 months later (4 months following policy change)). After the final wave of data collection in February 2019, further analyses will be conducted to evaluate the impact of codeine rescheduling in Australia.

Conclusions

Ahead of the rescheduling, there was substantial debate about the potential for negative effects on individuals and on health services from the policy change. Initial results suggest instead that engagement with health services has increased and use and dependence have declined without problematic substitution effects. Results from this study will contribute to an improved understanding of the negative and positive effects associated with the change, and will inform future approaches to regulatory restriction in relation to pharmaceutical opioids.