Newer antibiotics: guidelines for use.

The number of antimicrobial agents available for use has increased significantly since the introduction of penicillin in the mid 1940s. Consequently, choosing among them has become an increasingly complex problem. In selecting an antibiotic, careful consideration must be given to the status of the patient and to the organism isolated. In addition, the physician must have detailed knowledge about the specific characteristics of each agent and must apply basic guidelines of antimicrobial therapy in order to make a rational choice.