unused doses of medication. The data was collected by the Discover program and was analysed with GraphPad Prism. Results The media of patients in UDDDS per month was 251.1±19.09 and 245±20.90, with a total of 14 870 and 17 779 validated prescriptions in 2017 and 2018 respectively. The percentage of validated prescriptions before 3 pm was 71.79% in 2017 (PCC) in comparison with 86.95% in 2018 (AEP), supposing an increase of about 15.18%. The percentage of the returns of unused medication doses was 20.26±) 0.83 in 2017 versus 20.21±0.48 in 2018, not showing significant differences between the years of comparison. Conclusion Our results show a significant increase in the percentage of validation in the optimal schedule after the implementation of AEP despite the small increase in activity. Assuming that the remaining 12%-13% of the prescriptions correspond to changes in the treatment and hospital admissions during the afternoon and night, we consider we satisfied the purpose of the study. The parameter of the returns of unused medication doses, however, show the need for continuing the evaluation of the procedures in order to obtain a greater effectiveness. REFERENCES AND/OR ACKNOWLEDGEMENTSNo conflict of interest.