Sales of over-the-counter codeine-containing medicines in South Africa, 2019-2020: a retrospective observational study

Abstract

Introduction and Rationale Codeine-containing medicines (CCMs), used mostly for its analgesic properties, with its addictive potential, contributes to irrational drug use in South Africa (SA). Furthermore, many CCMs are affordable and some available as over-the-counter (OTC) medicines, thus increasing risks of misuse. This leads to misconceptions of codeine’s safety due to its easy accessibility. Analysing OTC CCM sales trends and associations in SA, can provide valuable information for policy reform. Aim The study aimed to review the factors contributing to CCMs. The dissertation further aimed to describe the sales trends of OTC CCMs using a retrospective observational analysis of an IQVIA dataset. The dataset included sales data from retail pharmacies across all provinces in SA for the period of 1 January 2019 to 31 December 2020. Objectives I. To conduct a review of the factors contributing to CCM sales. II. Objective II was divided into parts a and b. a. To describe the sales trends of OTC CCMs across all provinces in SA. b. To assess any difference between the effect of the severe acute respiratory syndrome-related coronavirus 2 (Covid-19) pandemic on the sales trends of OTC CCMs across all provinces in SA. III. To determine the contributing factors associated with OTC CCM sales in the South African provinces of Gauteng, Mpumalanga and the North-West, identified as “codeine hotspots”. Methodology A quantitative retrospective observational analysis of South African codeine-sales data, from an IQVIA dataset was used for analyses, using STATA®, to determine the sales trends and associations significantly associated with OTC CCM sales across all provinces in SA. An overview of the factors contributing to CCM sales was discussed. Pearson chi-square tests were used to determine evidence to support the presence of any associations between the analysed variables. Descriptive results were plotted in v graphs to depict the trends and effects associated with OTC CCM sales. Univariate and multiple linear regressions were also conducted to determine the strengths of the contributing factors associated with OTC CCM sales in the three South African “codeine hotspot” provinces (Gauteng, Mpumalanga and the North-West). Results In total, 36 065 459 OTC CCM script line items were analysed. Cumulatively, the top five OTC CCM products sold, accounted for approximately 60% of the total percentage distribution of all the analysed products. These included Adco-Dol® (40s) (21.34%), Mybulen® (30s) (12.80%), Gen-Payne® (30s) (10.78%), Adco-Dol® (20s) (10.02%) and Accurate® (40s) (7.93%). Gauteng (40.95%) descriptively displayed the greatest amount of OTC CCM sales, with the Northern Cape (2.35%) showing the least amount of OTC CCM sales. Sales were greatest through cash payments in chain pharmacy groups, at the onset of winter. March 2020 demonstrated a significant sales spike, before plummeting in April 2020, indicative that sales were higher before Covid-19, with significant differences (p<0.001). Of the “codeine hotspot” provinces (Gauteng, Mpumalanga and the North-West), linear regressions showed significant results, with Gauteng displaying increased OTC CCM sales (p<0.001), particularly with the sale of generic (p<0.001) oral liquid products (p<0.001), acquired with cash (p<0.001) and purchased as smaller pack sizes (p<0.001). Conclusion From this study's findings, codeine use is still greatly prevalent in SA. Legitimate and irrational use of OTC CCMs is affecting the burden of medicine misuse and abuse in SA. The purchase of oral liquid form OTC CCM products is on the rise, particularly amongst the adolescent generation, as an easy and affordable illicit drug. Purchasing affordable OTC CCMs with cash and in smaller pack sizes is prevalent in SA’s top three “codeine hotspot” provinces (Gauteng, Mpumalanga and the North-West). It is therefore recommended that enhanced education, knowledge, and codeine policy reform surrounding the control of access to OTC CCMs is warranted to help combat irrational CCM misuse in SA.