Objectives: To assess the effectiveness of a combined intervention on the timing and rate of switching from intravenous (IV) to oral antibiotic therapy. Materials and methods: The study used a historically-controlled prospective intervention design. Interventions consisted of educating physicians, handing out pocket-sized cards and providing switch advice in the electronic patient record (EPR). All patients hospitalized at the surgery department who were treated with IV antibiotics for at least 24 h and who fulfilled the switch criteria within 72 h of IV treatment were included. Outcomes before and during the intervention were compared. Results: An early IV to oral switch took place in 35.4% (35/99) of the antibiotic courses in the baseline period and in 67.7% (42/62) of the antibiotic courses in the intervention period (odds ratio [OR] 3.84, 95% confidence interval [CI] 1.96–7.53). Duration of IV therapy was significantly reduced from 5 to 3 days (P<0.01). Length of hospitalization was reduced from 6 to 5 days (P<0.05). Conclusions: The interventions were effective in promoting an early IV to oral antibiotic switch by shortening the length of IV therapy and hospital stay.