Commentary on McCoy et al.: More pieces of the mosaic describing outcomes of the Australian up-scheduling of over-the-counter codeine to prescription only.

Abstract

Data from the Australian Institute of Health and Welfare (AIHW) about trends in treatment and non-medical use of codeine and other opioids supports other recent studies indicating there has been no unintended harm from the February 2018 upscheduling of over-the-counter codeine to prescription only. Understanding the trends in non-medical use of pharmaceutical drugs and its consequences relies upon triangulating signals from different data sources to provide a mosaic overview [1]. McCoy et al.’s recent work forms an integral part of the picture in understanding outcomes from a major Australian opioid policy decision: the removal of codeine sales without a prescription [2]. The study examined those who regularly used codeine prior to the re-scheduling change and found reductions in codeine use, no increase in use of other opioids and reduced levels of opioid dependence following codeine re-scheduling. Small increases in general practitioner visits but a reduction in emergency department visits for opioids was also observed, alongside no change in mental health symptoms and an overall reduction in pain. These findings are consistent with work demonstrating a reduction in intentional poisonings with codeine [3], an analysis of population-level opioid supply showing no evidence of substitution to other opioids [4] and a study that found decreased codeine deaths, emergency department presentations and poisonings [5]. Collectively, these data sources provide a coherent picture indicating this policy change did not appear to have unintended harms. This may be linked to the substantial investment and implementation efforts that occurred at the time to raise awareness and support referral for pain management and alcohol and other drug treatment [6]. We write to describe the effects of up-scheduling using several sources provided by the AIHW, which represent a final piece of the puzzle. The National Drug Strategy Household Survey is conducted every 3 years. In 2016, past 12-month non-medical use of pharmaceuticals was the second leading category of drug misuse (4.8% of adults aged 14 or more years) after cannabis [7]. Non-medical use of painkillers/opioids was reported by 3.6% of the population: 29% misused painkillers/opioids at least weekly and 10.7% reported not being able to stop or cut back. Of those reporting misuse of painkillers/opioids, 74.8 and 40.6% reported non-medical use of OTC or prescription codeine, respectively. The prevalence of OTC codeine product misuse was highest in youths aged 14–19 years; 89% of those misusing painkillers/opioids reported this in the previous 12 months. In the 2019 survey, with codeine no longer available without a prescription, the proportion of people using codeine for non-medical purposes halved from 3.0% in 2016 to 1.5% [8]. The proportion of people who had recently misused pharmaceuticals decreased from 4.8% in 2016 to 4.2% in 2019. This included a decrease in the proportion of those recently misusing pain-killers/opioids from 3.6 to 2.7% during this period: of these, there was a statistically significant decrease in the proportion who had misused codeine, from 87.95% in 2016 to 60.7% in 2019. AIHW reports on episodes of care for clients seeking treatment from publicly funded Australian drug treatment services [9, 10] including reporting on trends where codeine was a drug of concern (Fig. 1). The number of codeine-related combined principal and additional drugs of concern closed episodes more than halved (51.1%), from 2711 in the last full financial year when codeine was available OTC (2016–17) to 1326 in the most recent year (2019–20). AIHW also reports standardized data concerning opioid agonist treatment with methadone or buprenorphine for the treatment of opioid use disorder [11]. From 2014 to 2020 heroin and pharmaceutical opioids accounted for 60–65% and 35–40% of the opioid of dependence, respectively (where reported). In the last calendar year (2017), when codeine was available OTC without a prescription, it accounted for 2095 cases (17.5% of all pharmaceutical opioids of dependence reported). This increased to 2332 (19%) in 2018, the first year following up-scheduling on 1 February 2018, and decreased each subsequent year to 2014 (15.7%) in 2020—the lowest proportion since 2015. The treatment and non-medical use data presented here support recent studies that indicate no evidence of unintended harms with codeine re-scheduling. This differs from that seen with re-scheduling of hydrocodone in the United States with a shift to other opioids [12]. This also contrasts with perceptions of pharmacists and consumers, and with concerns raised in submissions to the Therapeutic Goods Administration [13]. These findings may give the small number of countries who continue to supply codeine without a prescription confidence that, with appropriate implementation efforts, such a change can be made without adverse consequences for individuals and the community. Suzanne Nielsen was a co-author in the Addiction paper McCoy et al. to which we refer for this commentary.