The aim of the present study was to characterize the utilization of medicines by the Brazilian population, using data from the Brazilian World Health Survey. Medicines were grouped according to the active pharmaceutical ingredient based on an adaptation of the World Health Organization standard list of essential medicines. The analysis included the characteristics of individuals who keep medicines at home and who had used them within the reference period (within two weeks prior to the interview), according to presence of medical prescription. Nearly half of the participants (49.0%) reported use of medicines during the reference period. Older and wealthier individuals and those with chronic diseases or disabilities and with poor self-rated health keep and use medicines more frequently. For 25.0% of the individuals that had used medicines during the reference period, none of the drugs had been prescribed by a health professional. Among the individuals who had medicines prescribed in the last appointment, 13.0% were unable to obtain the prescribed medication (of these, 55.0% could not afford it). The most widely utilized group was that of the analgesics (22.0%), and only 51.0% of the individuals using this type of medicine had received a medical prescription for it.