Abstract: Objective To find out how sustained and controlled release preparations are used in the Affiliated Drum Tower Hospital of Medical School, Nanjing University, so as to provide reference for clinical rational use of drugs. Methods All the prescriptions related to sustained and controlled release preparations for inpatients in April 2019 were collected, and the rationality with which these sustained and controlled release preparations were used was analyzed retrospectively. Results There were something irrational about the use of sustained and controlled release preparations, such as incorrect dose segmentation, improper routes of medication, excessive frequency of administration, and repeated use of medicines. Conclusion It is suggested that prescriptions be reviewed by pharmacists in a standardized way and clinicians receive better training to improve the rationality of sustained and controlled release preparations, promote the rational use of clinical medicines and to ensure the safety of patients

Key words: sustained and controlled release preparation, rational administration, clinical application