The views of Australian adults experiencing pain on the upscheduling of codeine-containing analgesics to 'prescription only'

The impact of codeine rescheduling on non-opioid analgesic use by people who regularly use codeine: a prospective cohort study

BACKGROUND

Codeine was rescheduled in Australia to prescription only in February 2018. Initial studies reported an increase in population level paracetamol and ibuprofen sales following codeine upscheduling. However, to date no study has been able to investigate changes in non-opioid analgesic use at the individual patient level to determine if sales data reflect actual consumption patterns.

AIM

To address this gap, we aimed to determine the impact of codeine rescheduling on non-opioid analgesic use in people who regularly used over-the-counter codeine, primarily for pain, prior to the rescheduling change.

METHOD

We conducted a prospective cohort study with 260 participants who reported regular over-the-counter codeine consumption at cohort entry. Surveys were completed at baseline (November 2017, 3 months before rescheduling) and at 1 month (February 2018), 4 months (June 2018), and 12 months (February 2019), following rescheduling. The primary outcomes were mean daily doses of non-opioid analgesics, captured through a 7 day medication diary.

RESULTS

The mean daily paracetamol dose decreased from 1754.4 mg (95% CI 1300.5-2208.3) at baseline to 1023.8 mg (95% CI 808.5-1239.1) at the final time-point (+ 12 months) (p = .009). The mean daily ibuprofen dose decreased from 305.1mg (95% CI 217.9-392.4) at baseline to 161.2 mg (95% CI 98.5-224.0) 12 months after rescheduling (p = .03). No significant change in doses of other medications remained was found.

CONCLUSION

In people who regularly consumed over-the-counter codeine, doses of non-opioid analgesics either reduced or remained stable following codeine rescheduling, suggesting concerns of medication substitution or overuse following the change were not realised.

A genome-wide Association study of the Count of Codeine prescriptions

Opioid prescription records in existing electronic health record (EHR) databases are a potentially useful, high-fidelity data source for opioid use-related risk phenotyping in genetic analyses. Prescriptions for codeine derived from EHR records were used as targeting traits by screening 16 million patient-level medication records. Genome-wide association analyses were then conducted to identify genomic loci and candidate genes associated with different count patterns of codeine prescriptions. Both low- and high-prescription counts were captured by developing 8 types of phenotypes with selected ranges of prescription numbers to reflect potentially different levels of opioid risk severity. We identified one significant locus associated with low-count codeine prescriptions (1, 2 or 3 prescriptions), while up to 7 loci were identified for higher counts (≥ 4, ≥ 5, ≥6, or ≥ 7 prescriptions), with a strong overlap across different thresholds. We identified 9 significant genomic loci with all-count phenotype. Further, using the polygenic risk approach, we identified a significant correlation (Tau = 0.67, p = 0.01) between an externally derived polygenic risk score for opioid use disorder and numbers of codeine prescriptions. As a proof-of-concept study, our research provides a novel and generalizable phenotyping pipeline for the genomic study of opioid-related risk traits.

Elevating Safe Use of Over-The-Counter Medications in Older Adults: A Narrative Review of Pharmacy Involved Interventions and Recommendations for Improvement

Over-the-counter (OTC) medications are products that have been made easily accessible to allow patients to treat common ailments without a prescription and the cost of a doctor's visit. These medications are generally considered safe; however, there is still a potential for these medications to lead to adverse health outcomes. Older adults (ages 50+) are especially susceptible to these adverse health outcomes, due to age-related physiological changes, a higher prevalence of comorbidities, and prescription medication use. Many OTC medications are sold in pharmacies, which provides pharmacists and technicians with the opportunity to help guide safe selection and use for these medications. Therefore, community pharmacies are the ideal setting for OTC medication safety interventions. This narrative review summarizes the findings of pharmacy-involved interventions that promote safe OTC medication use for older adults.

A wastewater-based evaluation of the effectiveness of codeine control measures in Australia

BACKGROUND AND AIM

From 1 February 2018, codeine was rescheduled from an over-the-counter (OTC) to a prescription-only medicine in Australia. We used wastewater-based epidemiology to measure changes in population codeine consumption before and after rescheduling.

METHODS

We analysed 3703 wastewater samples from 48 wastewater treatment plants, taken between August 2016 and August 2019. Our samples represented 10.6 million people, 45% of the Australian population in state capitals and regional areas in each state or territory. Codeine concentrations were determined by liquid chromatography-tandem mass spectrometry and converted to per-capita consumption estimates using the site daily wastewater volume, catchment populations and codeine excretion kinetics.

RESULTS

Average per-capita consumption of codeine decreased by 37% nationally immediately after the rescheduling in February 2018 [95% confidence interval (CI) = 35.3-39.4%] and substantially in all states between 24 and 51% (95% CI = 22.4-27.0% and 41.8-59.4%). The decrease was sustained at the lower level to August 2019. Locations with least pharmacy access decreased by 51% (95% CI = 41.7-61.7%), a greater decrease than 37% observed for those with greater pharmacy access (95% CI = 35.1-39.4%). Regional areas decreased by a smaller margin to cities (32 versus 38%, 95% CI = 30.2-34.1% versus 34.9-40.4%, respectively) from a base per-capita usage approximately 40% higher than cities.

CONCLUSION

Wastewater analysis shows that codeine consumption in Australia decreased by approximately 37% following its rescheduling as a prescription-only medicine in 2018. Wastewater-based epidemiology can be used to evaluate changes in population pharmaceutical consumption in responses to changes in drug scheduling.