The use of pharmaceuticals requires establishing a safe environment and securing a system to reduce risk. In our isotope inspections, the operational system for using radiopharmaceuticals was insufficient, which became a problem. For this reason, through cooperation between a radiological technologist responsible for radiation safety management and a pharmacist responsible for medicine safety management, we considered the operational system for the preparation and management of radiopharmaceuticals at our hospital. In accordance with the guidelines for handling radiopharmaceuticals, we established a system to reduce risks by reviewing pharmaceuticals, creating checklists, and improving the work environment. By reviewing and improving the system of safety management and safe use in cooperation with other disciplines, it became possible to reduce risk through double checks and to improve the work environment for routine operations. This report describes the efforts made in our hospital.