BackgroundTimely switch from intravenous (iv) antibiotics to oral therapy is a key component of antimicrobial stewardship programs in order to improve patient safety, promote early discharge and reduce costs. We have introduced a time-efficient and easily implementable intervention that relies on a computerized trigger tool, which identifies patients who are candidates for an iv to oral antibiotic switch.MethodsThe intervention was introduced on all internal medicine wards in a teaching hospital. Patients were automatically identified by an electronic trigger tool when parenteral antibiotics were used for >48 h and clinical or pharmacological data did not preclude switch therapy. A weekly educational session was introduced to alert the physicians on the intervention wards. The intervention wards were compared with control wards, which included all other hospital wards. An interrupted time-series analysis was performed to compare the pre-intervention period with the post-intervention period using ‘% of i.v. prescriptions >72 h’ and ‘median duration of iv therapy per prescription’ as outcomes. We performed a detailed prospective evaluation on a subset of 244 prescriptions to evaluate the efficacy and appropriateness of the intervention.ResultsThe number of intravenous prescriptions longer than 72 h was reduced by 19% in the intervention group (n = 1519) (p < 0.01) and the median duration of iv antibiotics was reduced with 0.8 days (p = <0.05). Compared to the control group (n = 4366) the intervention was responsible for an additional decrease of 13% (p < 0.05) in prolonged prescriptions.The detailed prospective evaluation of a subgroup of patients showed that adherence to the electronic reminder was 72%.ConclusionsAn electronic trigger tool combined with a weekly educational session was effective in reducing the duration of intravenous antimicrobial therapy.Electronic supplementary materialThe online version of this article (doi:10.1186/s13756-017-0239-3) contains supplementary material, which is available to authorized users.