General Principles of Antibiotic Therapy

The essential feature of effective antibiotic agents is the ability to inhibit the growth of microorganisms at concentrations tolerated by the host. Antibiotic agents generally target anatomic structures or biosynthetic pathways unique to bacteria. The appropriate choice of an antibiotic for an infection depends on the following: clinician’s level of suspicion; the infecting organism and its antibiotic susceptibilities; the type of infection; factors associated with specific antibiotic agents; host factors; and public health considerations. This review provides an overview of antibiotic therapy and covers identifying the cause of an infection, determination of bacterial susceptibility to specific drugs, site of infection and ancillary therapy, antibiotic drug targets, pharmacodynamic parameters, factors affecting dosage and route of administration, host factors, complications of antibiotic therapy, Clostridium difficile infection, and antimicrobial resistance.  This review contains 2 figures, 7 tables, and 45 references. Key words: Antimicrobial therapy, antibiotic, infection, microorganism, renal dosing, hepatic dosing, Clostridium difficile