Background Pharmaceutical Interventions (PI) are part of pharmaceutical care process and aim to reduce drug-related negative results through early detection of drug related problems (DRP). They are mainly focused on renal/hepatic adjustment of drugs, and supervision of medicines with narrow therapeutic windows and unconventional regimen features.

Purpose Evaluation of PI in separate departments during the first semester of 2011. This will allow a consistent and uniform record and classification of PI, aiming to raise doctors' awareness for the most frequent prescription-related DRPs.

Materials and methods PI's were recorded on a database (Excel 2007) and classified according to the DÁDER method (Third Revision 2005-University of Granada), accepted as a tool to identify DRPs. DRPs are classified according to: Need: DRP1-Need of additional treatment and DRP2-Unnecessary drug; Efficacy: DRP3-Non-quantitative lack of efficacy and DRP4-Quantitative lack of efficacy; Safety: DRP5-Non-quantitative insecurity and DRP6-Quantitative insecurity.

Results From a total of 1835 PI, 82% were accepted (AC). The DRP's distribution was: DRP1-17, 4%, DRP2-25, 4%, DRP3-2%, DRP4-16, 1%, DRP5-5, 1%, DRP6-33, 5%. Departments were analysed separately because of different specifications. The medicine department had a total of 795 PI, with an acceptance of 80, 4%. The most frequent DRP's were DRP6 (38%), DRP1 (20%) and DRP2 (19%). The surgical department had 470 PI, with an acceptance of 95, 5%. The most frequent DRP's were DRP2 (42,2%), DRP6 (19,9%), DRP1 (18,6%) and DRP4 (17,2%). Intensive care units had a total of 149 PI with 89, 3% accepted, the most frequent being DRP6 (40,4%) and DRP4 (31, 5%). The emergency department had a total of 421 PI with 67% accepted. The most frequent DRP's were DRP6 (37%) and DRP2 (24%).

Conclusions This analysis showed that:

• ▶ The pharmaceutical interventions had high rates of acceptance (≥80%)

• ▶ The most frequent DRP were related to quantitative insecurity (DRP6), followed by the prescription of unnecessary drug (DRP2), despite some differences between different departments.