Objective: To understand the predisposing factors that lead to the practice of self-medication and the factors associated with the use of medicines via self-medication in the adult population of Brazil.
Methods: The analyzed data are part of the National Survey on Access, Use and Promotion of Rational Use of Medicines (PNAUM), a survey whose population consisted of individual residents permanently domiciled in urban areas in Brazil. In this work, the data references the 31 573 respondents aged 20 or higher (76.2% of the final PNAUM sample). Poisson regression models with robust variance were used for estimating the independent effect of each variable with medicine use via self-medication.
Results: Of the interviewees, 73.6% stated they had used some medication without medical recommendation if they had previously used the same product; 73.8% stated they had used non-prescribed medicine when the medicine was already present at home; and 35.5% stated they had used some non-prescribed medication when they knew someone who had already taken the same medication. The prevalence of self-medication was 18.3%. The variables associated with the highest probability of using medicine via self-medication were: geographic region within Brazil, gender, age group, per capita income, self-assessment of health, self-reported use of previously used non-prescribed medication, and self-reported use of non-prescribed medication when that medication was already present at home.
Conclusions: The use of medicines via self-medication in Brazil is relatively frequent and influenced by previous experience and familiarity with the medications, and is more common among women and individuals with low self-assessment of health.