General principles of antimicrobial therapy

Use of antimicrobial agents must be tailored to the individual patient, site of infection, and etiologic organism. The choice of drug should be based on efficacy, safety, low toxicity, and acceptable cost. Empiric therapy should be broad enough to cover the pathogens that are suspected of causing the infection, based on the site of infection and the type of host. Definitive therapy may differ from initial therapy and should be started as soon as specific laboratory and clinical data are available. Cautious conservatism is advocated with regard to the use of new antimicrobial agents. The effects of the agents on the microbial ecology and hospital environment should be considered. Judicious use is necessary to prevent antimicrobial pollution.