Dispensing errors may cause serious health damage. To eradicate dispensing errors, we implemented new safety management strategies, including the development of a dispensingsupport system with a computerized check function. We previously evaluated and reported the usefulness of these new strategies for safety management by comparing the incidence of potential adverse drug events (PADEs) before and after the implementation of these strategies. In the present study, we compared the incidence of PADEs from outpatient prescriptions in the late phase 5 years after the start of the new safety management program with that before the implementation. The incidence of PADEs from outpatient prescriptions after the start of these strategies (late phase) was significantly lower than that before their introduction (p<0.001), similar to the results in the early phase. When examining PADEs with respect to category, the incidence of PADEs related to the dispensing of a wrong drug, such as those related to errors in the drug name or standard/dosage form of the same drug, in the late phase was significantly lower than that before the new program began (p<0.05), as was also the case in the early phase. The incidence of PADEs related to errors in counting tablets/capsules was also significantly lower (p<0.01, p<0.05). With respect to the level of influence on patients (level O to 3a), the incidence of level-O PADEs, which represents potential errors that were prevented, in the late phase was significantly lower than that before implementation (p<0.01), as was also demonstrated in the early phase. The incidence of level-1 PADEs in the late phase was significantly lower than that before implementation (p<0.05), but not in the early phase. No level-2 or higher PADE occurred in the early or late phases after the start of the new safety program. When the PADEs were examined with respect to possible contributing factors, the incidences of PADEs associated with the presence of multiple standards in the early and late phases were significantly lower than that before (p<0.05). These results suggest the long-term usefulness of this series of newly introduced strategies for safety management.