Cost-effectiveness and value of an IV switch

A few antibiotics (i.e. metronidazole, clindamycin and ciprofloxacin) are available in both parenteral and oral formulations, and have good bioavailability, ensuring equivalent systemic drug concentrations. During a 4-year period subsequent to the initiation of a parenteral to oral (IV-PO) stepdown programme for metronidazole and clindamycin, Vancouver General Hospital saved approximately $C85 000. However, many parenteral antibacterials lack an oral formulation, requiring oral stepdown to a different antibacterial with a similar spectrum of activity. Alternatively, the oral formulation of a parenteral antibacterial may have poor bioavailability (i.e. cefuroxime axetil, ampicillin, cloxacillin, erythromycin, and tetracycline) and it is not possible to maintain equivalent systemic drug concentrations. While rigid criteria are not applicable to all clinical scenarios, the general criteria for oral stepdown include the following: the patient 1) continues to need an antibiotic; 2) is clinically stable; 3) is capable of tolerating the oral dosage form; and 4) has no factors present (e.g. gastrointestinal abnormalities or drug interactions) that would adversely affect oral bioavailability. A review of subsequent IV-PO stepdown programmes at Vancouver General Hospital revealed that 1) not all patients receiving parenteral therapy are candidates for oral stepdown; 2) oral stepdown is delayed in a large proportion of treatment courses; 3) oral stepdown is not occurring in many patients for whom it is deemed appropriate; and 4) in a very few treatment courses stepdown may occur prematurely and may contribute to clinical deterioration.(ABSTRACT TRUNCATED AT 250 WORDS)