Background and importance Therapeutic equivalents are drugs with a different chemical structure but with similar therapeutic and adverse effect profiles when equivalent doses are administered.

Aim and objectives To analyse the pharmacotherapeutic interventions of proposing therapeutic equivalents (PIPTEs) for prescribed not included in the pharmacotherapeutic guide medications (NIGM), as well as their degree of acceptance.

Material and methods A retrospective observational study was carried out over a period of 2 months. The PIPTEs were realised during pharmaceutical validation. The following items were collected: age, sex, prescribed NIGM, acceptance of the PIPTE (it was considered accepted when changes were generated in the prescription), measure adopted by the doctor (change to the proposed equivalent, change to another equivalent, patient contribution or suspension of treatment) and the medical service.

Results A total of 211 patients (122 men) with a median of 76 years (20–98 years) were reviewed. A total of 2197 interventions were performed: 1294 (58.9%) were about NIGM. Of these, 228 (17.62%) were PIPTEs, with the following distribution according to pharmacotherapeutic group: 78 (34.21%) ARA-II, 65 (28.5%) ACEIs, 34 (14.91%) statins, 32 (14.05%) calcium antagonists, 5 (2.19%) PPIs, 1 (0.44%) anti-H2 and 13 (5.7%) of other groups.

Most of the PIPTEs were accepted (79.82% (182)). The degree of acceptance of each pharmacotherapeutic group was: 79.49% (62) for ARA-II, 89.23% (58) for ACEIs, 73.53% (25) for statins, 75.0% (24) for calcium antagonists, 40.0% (2) for PPIs, 100% (1) for anti-H2 and 69.23% (9) for other groups.

In 52.19% (95) of cases, the proposed therapeutic equivalent was changed (25 ARA-II, 41 ACEIs, 13 calcium antagonists, 10 statins, 2 PPIs, 1 anti-H2 and 3 other groups). In 25.82% (47) of patients the drug was contributed by the patient, 14.84% (27) were suspended and 7.14% (13) were changed to a drug different from the one proposed.

Conclusion and relevance The majority of the interventions performed by pharmacists were in relation to NIGM. ARA-II and ACEIs were the groups with the highest number of PIPTEs. More than 75% of the PIPTEs caused a change in the prescription, which resulted in more than 50% of cases substituting the NIGM for the equivalent proposed by the pharmacy service. This reflects the great contribution of the hospital pharmacist to therapeutic exchange programmes.

References and/or acknowledgements No conflict of interest.