Switch therapy: the theory and practice of early change from parenteral to non-parenteral antibiotic administration.

OBJECTIVE: The idea behind switch therapy is that antibiotic treatment should be changed from the parenteral to another suitable route (usually oral) as soon as the patient's condition allows. This option is cost-effective in terms of both acquisition costs (oral antibiotics are less expensive than their parenteral counterparts) and indirect costs, and patients may be discharged home sooner. This not only releases hospital beds but is also popular with patients and has other advantages. There are relatively few formal clinical trials, most often using oral third-generation cephalosporins and fluoroquinolones; these agents at present seem the most appropriate to use after parenteral antibiotics have been stopped (usually after 2 to 3 days). Logistic aspects are important, and close collaboration is required between pharmacists, physicians and microbiologists. Further trials are needed in specific patient groups and with other antibiotic regimens to validate the efficacy of switch therapy.