Evaluation of policies and practices to support safe and appropriate analgesic and sedative prescribing: The CDRx (controlled drug prescribing) protocol

Medications provide many therapeutic benefits; however, these must be balanced against the potential for patient harm. Two high-risk medications are benzodi-azepine receptor agonists or BZRAs (including benzodiazepines and Z-drugs hypnotics) and opioid analgesics, which carry a risk of dependence, misuse, and abuse. Use of these medications has been growing internationally, along with associated morbidity and mortality. These medications are often classified as 'controlled drugs' and subject to legal restrictions in order to balance therapeutic benefits and risks of misuse. The aim of this project is to evaluate prescribing of analgesic and sedative drugs, in particular opioid and BZRA medications, to characterise time trends, the impact of policy changes, and regional and GP practice variation. This will be addressed across three workpackages, primarily using data on prescriptions dispensed to individuals eligible for the General Medical Services scheme in Ireland, held by the HSE Primary Care Reimbursement Service, along with other national and in-ternational data collections. Workpackage 1 will derive volume and patterns of utilisation indicators of controlled drugs and related medications and describe time trends in primary care in Ireland between 2014 and 2021 in two repeated cross-sectional studies. Workpackage 2 will consist of two interrupted time series studies on the impact of recent policy changes on prescribing. Workpackage 3 is a cohort study of GP practices, which will aim to quantify and explain regional and GP practice-level variation in analgesic and sedative prescribing, and, in relation to policy changes. This research will provide data-driven insights to inform policy-makers' decisions and clinical practice to optimise regulation and use of these medications for the benefit of patients and society.