Introduction: Psychiatric disorders have become a global problem that leads millions of people to use psychotropic medications, especially benzodiazepines. The effects of these substances are widely known regarding tolerance and chemical dependence, however, from epigenetics perspective, there are still little known.
 Objective: To evaluate the association between psychotropic drug use, NR3C1 gene methylation and its relation with symptoms suggestive of depression in adult individuals assisted in the public health system.
 Methods: 385 adult volunteers (20-59 years) users of the Brazilian Unified Health System were recruited to evaluate socioeconomic, health, lifestyle conditions in a cross sectional study. BDI-II evaluated symptoms suggestive of depression and pyrosequencing evaluated NR3C1 DNA methylation. Bivariate and multivariate Poisson regression model with robust variance (p < 0.05) evaluated the association between psychotropic drug use and NR3C1 gene methylation.
 Results: Specific depressive symptoms such as irritability, insomnia and fatigability were associated with psychotropic drug use. Symptoms of past failure, indecision and loss of appetite were associated with hypermethylation patterns in CpGs 40 to 47 of NR3C1 gene. Moreover, psychotropic drug use is associated with 50% reduction in NR3C1 gene methylation, through model adjusted with socioeconomic, health and lifestyle confounding variables.
 Conclusions: Psychotropic drug use and depressive symptoms was associated with changes in NR3C1 DNA methylation. In this context, epigenetic modification resulting from psychotropic drug use and depressive symptoms could be considered, mainly in population studies with epigenetic evaluation, where these factors may be influencing the findings of future studies.
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