Long-term antibiotic cost savings from a comprehensive intervention program in a medical department of a university-affiliated teaching hospital.

We tested a low-cost, multifaceted intervention program comprising formulary restriction measures, continued comprehensive education, and guidelines to improve in-hospital use of antibiotics and related costs. In a short-term analysis, total antibiotic consumption per patient admitted, which was expressed as defined daily doses (DDD), decreased by 36% (P < .001), and intravenous DDDs decreased by 46% (P < .01). Overall expenditures for antibiotic treatment decreased by 53% (100 US dollars per patient admitted). The 2 main cost-lowering factors were a reduction in prescription of antibiotics (35% fewer treatments; P < .0001) and more diligent use of 5 broad-spectrum antibiotics (23% vs. 10% of treatments; P = .001). Quality of care was not compromised. A pharmacy-based, prospective, long-term surveillance of DDDs and costs over 4 years showed an ongoing effect. This comprehensive intervention program, which aimed to reduce antibiotic consumption and costs, was highly successful and had long-lasting effects.