Abstract The rational use and disposal of medicines is a topic that has been discussed by researchers worldwide, aiming to minimize the consumption and indiscriminate use of these compounds. The objective of this work was to promote the study of rational use, informative and educational action and environmental risks due to inadequate disposal. The proposal for this study was forwarded to the Institution's Ethics Committee, linked to the study, and its realization was approved, CAAE: 91559018.9.0000.5490, Opinion Number: 2,751,853. Data collection was carried out through an interview, through a questionnaire, evaluating aspects, regarding the rational use and disposal of medicines, having been developed in the city of Jaguariuna-SP. The research assessed the level of knowledge of a group, in relation to rational use, disposal of leftovers and expired medicines and knowledge about the potential effects on the environment and public health arising from these actions. It was found that almost all respondents have medicines at home, 50.93% of which are overdue, however the lack of information regarding the correct form of disposal, causes the population to proceed inappropriately. Among the main reported destinations, storage and disposal in common garbage prevails. Regarding awareness and responsibility, with regard to environmental contamination, more than 70% are aware of the problems caused in the environment and public health. Finally, regarding educational and informational actions in relation to the storage and disposal of medicines, 65.22% of the interviewees stated that they had not previously received any type of information on the proper storage and disposal of medicines. The data demonstrate the interviewees: awareness of the environmental and public health problems that may eventually be triggered due to the aspects addressed. However, the lack of information and adequate posts makes it difficult to disseminate information. Key messages The lack of guidance on storage and disposal of medicines, as well as aspects related to rational use, was the main aspect observed. It is necessary to take effective action regarding the inappropriate disposal of drugs in the environment, given the potential risk to public health arising from this practice.