Background and Importance Interdisciplinary collaboration, particularly involving pharmacists in medication reconciliation, can prevent errors. Medication discrepancies at care transitions are common and linked to adverse events that’s why addressing communication barriers before errors happen is crucial.

Aim and Objectives This study aims to analyse the prescription of medication not included in the hospital’s pharmacotherapeutic guide (MNIG) and the pharmaceutical interventions (PI) performed.

Additionally, this research evaluates the effectiveness of a quality indicator aimed at reducing MNIG prescriptions in the cardiology service through PI.

Material and Methods A prospective study was conducted from 20 April to 31 August 2023, utilising the Farmatools® program to assess the following variables:

• The percentage of MNIG prescriptions, categorised by therapeutic group (TG) based on ATC codes.

• The cause of MNIG prescriptions, including reconciliation and new treatment.

-Number of substitutions in the therapeutic exchange program (TEP) resulting from PI, including the percentage of MNIG replaced by therapeutic equivalents (TE), discontinued, not substitutable, and included in the hospital guideline.

Results 322 MNIG were prescribed: 13% G04C, 12% B01A, 11% A10BD, 10% C10B, and the remaining 54%, miscellaneous drugs.

As for the cause of prescription: 95% is conciliation and 5% is prescription of a new treatment.

Of the MNIG prescribed, 53.4% had TE in the TEP, 18% were substituted, and the rest were provided by the patient. A total of 26.4% were not substitutable, and 11.18% were included in the hospital pharmacotherapeutic guide (HPG) and 9% were recommended to be suspended on admission, as indicated by the TEP.

The prescription of MNIG is variable during the months studied, with a median of 4%, maximum of 7.5% and minimum of 2%, with concerning the total number of prescriptions, without a linear trend.

Conclusion and Relevance The multidisciplinary team responsible for the patient should be involved in the reduction of MNIG to avoid medication errors, through the use of HPG and TEP.

Regarding the analysis of the indicator, we consider it important to perform PI to raise awareness among physicians of the correct use of NID, although we cannot confirm that the punctual decreases in prescriptions are due to the PI performed. In addition, the pharmacy service should review the HPG and TEP to include the necessary drugs and to disseminate the PET among health professionals.

Conflict of Interest No conflict of interest.