Evolution of Fentanyl Prescription Patterns and Administration Routes in Salamanca, Spain: A Comprehensive Analysis from 2011 to 2022

IntroductionThe escalating use of opioids poses a multifaceted challenge, contributing to social, health, and economic crises. In Spain, a notable surge in the medical prescription of opioids in recent years has been observed. In response to this growing concern, the Spanish Agency for the Regulation of Medicines and Healthcare Products issued an alert in 2018 regarding the misuse of opioids. ObjectiveThe aim of this research work was to assess the consumption rate of fentanyl, categorized by the different administration routes, in the province of Salamanca (Spain) spanning the years 2011 to 2022, and also to compare this local trend with the national scenario and with data published in the United States. Material and MethodsData on fentanyl consumption in the province of Salamanca, measured in defined daily doses (DDD), were sourced from the Regional Health System Registry in Castilla y Leon for each administration route from 2011 to 2022. Doses per inhabitant per day (DHD) were calculated, and interannual variations, as well as consumption rates, were subject to thorough analysis. Results and discussionThe prevalence of fentanyl use in Salamanca has surged from 1.2 DHD in 2011 to 2.56 DHD in 2022, with the transdermal system (TD) as the predominant administration route. This upward trajectory shows a positive correlation, mirroring the national trend, yet the rise in fentanyl usage is markedly lower than the reported data in the US. This finding may be attributed to an ageing population, and potentially inappropriate fentanyl prescriptions, i.e. for the management of chronic non-cancer pain and other off-label prescriptions. ConclusionThe use of fentanyl in Salamanca, particularly through transdermal systems, has doubled from 2011 to 2022, aligning with the national trend. Urgent preventive measures are imperative to prevent fentanyl misuse and moderate the observed escalation in consumption rates.