Opioids play an essential role in the management of moderate to severe pain and are commonly used in the hospital setting and provided on discharge. However, there is potential for unintended harm from opioid prescribing, particularly if this prescribing perpetuates longer-term opioid use. The overarching aim of this thesis is to investigate rates of persistent opioid use following hospital discharge in Australia and to explore opioid prescribing in Queensland. Chapter 2 is a systematic review of Australian literature which provides an estimate of persistent opioid use following hospital discharge. The results of the review primarily described persistent opioid use in the adult surgical setting, for which rates of persistent use generally ranged from 3.9-10.5% at between two and four months after discharge. There was limited literature identified for non-surgical hospital settings. Chapter 3 describes a study to compare outcomes when simple analgesia was supplied to patients receiving opioids at discharge from the emergency department, compared to standard practice of providing advice to take simple analgesia. It was expected, based on similar literature in day procedure settings, that this would improve pain management and reduce opioid use. Unfortunately, due to the impacts of the COVID-19 pandemic around the time the plan for the RCT was being finalised, the study could not be completed. Chapter 4 uses a Queensland drugs of dependence database available from 2008 to 2018 to characterise changes in opioid dispensing rates across Queensland. This was explored for individual opioid medicines, including when accounting for oral morphine equivalent, and rates of dispensing by age. It was found that while overall dispensing has started to decrease in recent years, that when accounting for OME, the amount of opioids entering the community continues to increase. Geographical differences in opioid dispensing showed that outer regional areas had the highest rates.