OBJECTIVES: Demonstrate possible savings by expanding the responsible use of OTCs (over-the-counter or nonprescription drugs) in Brazil in the public perspective.  METHODS: : Measure the volume and medical costs on public health system emergency and usage of OTC medicines. Data were obtained from the DATASUS system (030106006), SIGTAP 3.01.1.1.3, and research CHPA / USA January 2012 and adopted the premise of 10% OTC in the treatment of common diseases (common flu, allergy, and pain), to identify the average ticket cost on OTC consumption were used IMS Health of 2013 data and for absenteeism costs were used the Brazilian Ministry of work and IBGE data.  RESULTS: It was estimated that 8% (5,101,692) of all emergency attendances in SUS 2013 resulted in prescriptions that exhibited OTC medicines to treat common diseases, at a cost of 56 million,costs related to improductible days at BRL 369 million and expenditure in the acquisition of these drugs at BRL 61 million. CONCLUSIONS: The responsible use of OTC medicines can reduce up to 21% the volume of emergency attendances, and for every BRL 1 spent with OTC drugs is equivalent to an economy of BRL 7 in the public health system by reducing emergency visits and improductible days. The self-care, if done properly, can be an important factor in the improvement of public health, increasing productivity and reducing costs, in addition to providing more time for health professionals in the care of more complex cases. Notwithstanding the expansion of OTC drugs usage should be conducted responsibly with quality products and effective pharmaceutical care.