The aim of this study was to determine the effect of multifactorial, multidisciplinary educational interventions over a 3-year period on the appropriate use of teicoplanin. Teicoplanin was considered a valid surrogate marker of good antibiotic use in clinical practice owing to its peculiar pharmacokinetics (i.e. necessity for an initial loading dose regardless of the patient's renal function for early achievement of optimal exposure, namely C(min) > or = 10 mg/L) and to the opportunity of comparing current routine therapeutic drug monitoring (TDM) results with those of a historical retrospective study. A significantly higher proportion of patients received appropriate loading doses of teicoplanin in the present prospective study than in the retrospective study, both when considered as a whole (66.6% versus 38.6%, respectively; P<0.001) or when stratified according to the degree of estimated renal function (78.4% versus 60.4% for creatinine clearance (CL(Cr)) > 50 mL/min; 59.8% versus 26.8% for CL(Cr) 20-50 mL/min; and 27.7% versus 5.5% for CL(Cr) <20 mL/min). The highest adherence was observed in haematological wards (97.7%). The percentages of patients with teicoplanin C(min) > or = 10 mg/L during the treatment period in the present and retrospective study, respectively, were: 61.4% versus 3.2% on Day 2; 88% versus 35% on Day 4; 94% versus 70% on Day 7; and 99% versus 90% on Day 11. Our findings suggest that continuous application of a multifactorial educational programme including active TDM may be efficacious in improving and maintaining over time the appropriate use in a hospital setting of a theoretically difficult-to-use drug such as teicoplanin.