The authors tested the effectiveness and estimated the cost of several interventions aimed at reducing drug interactions in primary care by designing a 15-month cluster-controlled trial. The trial involved 265 family physicians and their patients who were randomized into 4 groups: control, report (received feedback reports), session (group sessions), and face-to-face (personal interviews). The outcome was the mean of relevant interactions detected on electronic medical records. Cost-effectiveness was defined as the incremental cost to reduce drug interactions by 1%. The authors detected a baseline mean of 6.7 interactions per 100 patients, which was reduced to 5.3 interactions after follow-up. No improvement was seen in the report group when compared with the control group, whereas progressive improvement in the other groups was noted (P < .001). Incremental cost was higher in the face-to-face group (69.4€ vs 50.7€); cost-effectiveness results were slightly better in the session group (4.2€ vs 4.5€).

1 in 20 Spanish citizens is currently undergoing a potential drug interaction, including a high rate of clinically relevant ones that should be avoided. These results confirm the existence of a serious safety issue that should be approached and where all parties involved (physicians, health services, medical societies and patients) must do our bit to improve. Health services should foster the implementation of prescription alert systems linked with electronic medical records including clinical data.

The use of antihypertensive drugs in Murcia is less than in the rest of Spain. Therefore, this may be due to a problem of under treatment of this illness or other cardiovascular illnesses in the region. A greater use of ARB in Murcia and a lower use of ACEI was observed in Murcia. The differences found suggest that further studies are required to clarify their origins and causes, with the objective of achieving a more rational and efficient use of these drugs.

e-PIG is a logarithmic expression of the risk that prescribing a particular drug may produce a severe interaction in a determined setting and time. Its monitoring could become a prioritisation element that may assist the design of strategies for improving the safety of the use of drugs.

No abstract