BackgroundSuicide is a global health concern whose rates are soaring in many low-and-middle-income countries. Public awareness campaigns have been implemented in Brazil; however, their impact is uncertain. MethodsThis was an ecological study using population data from DATA-SUS, a Brazilian official notification system, selecting only deaths that were voluntarily self-inflicted (CID-10 × 60-X84). We analyzed all available data from 2000 to 2019 to assess trends before and after the national Yellow September (YS) campaign started in 2015. Differences in trends were assessed by Joinpoint Analysis (JA) and Regression Discontinuity Analysis (RDD), unadjusted and adjusted for economic factors. ResultsOverall, there was a progressive increase in the rate of relative (per 100,000 inhabitants) number of suicides over time between 2000 and 2019 (57 % increase). The JA detected a change in the slope of the curve representing an acceleration in suicides starting in the year 2015. Adjusted RDD revealed the year that Yellow September started significantly change the slope of the association between time and rates of suicide (pinteraction < 0.01), and marginal analysis detected the coefficient increased from 0.07 (95%CI 0.04–0.10) to 0.27 (95%CI -0.07-0.60) suicides/year per 100,000 inhabitants. LimitationsThe ecological nature of the manuscript compromises causational implications. ConclusionsWe found an increase in suicidal trends in Brazil, against the global trend that coincides with the beginning of a large national awareness campaign. Although we cannot attribute causality, our results reinforce the need of further studies to better understand the role of awareness campaigns in suicide reduction interventions, including potential unintended effects.