The use of technology to support information produced by nurses, especially information and communication technologies, is a current reality, but the proliferation of different statements of nursing diagnosis has made it more difficult for the production of indicators, hindering semantic interoperability of data. This study analyzed all statements of diagnosis focused on the management of medication regimen, customized to the Nursing Practice Support System (SAPE®) that was being used in Portugal in 2013. A total of 598 statements of nursing diagnoses about the phenomenon under study were analyzed, through an a priori analysis model - the ISO 18104 standard: 2003. The purpose was to identify terms used by nurses to describe the range of diagnoses, thus avoiding conceptual redundancy. After a content analysis process conducted by researchers and a broader group of experts, and when excluded all conceptual redundancy, 30 statements of nursing diagnosis were identified.