Choosing cephalosporins for the formulary

Proper selection of antibiotics for any formulary requires cooperation and communication with members of the pharmacy and therapeutics (P&T) committee and departments of infectious diseases, microbiology, and epidemiology. Ideally, P&T members need to know their institution's incidence and sources of infection (hospital- or community-acquired), antibiotic cure rates, and the adverse effects profiles of antimicrobial agents used. In addition, members need to be briefed on the findings of antibiotic utilization reviews performed. In vitro activity should be compared among similar classes of antibiotics and, when possible, local resistance rates should be considered. The pharmacokinetic properties of an antibiotic, such as peak concentration, protein binding, distribution characteristics, and elimination half-life, should be evaluated during the selection process, as should total cost of the drug, including costs associated with monitoring therapy. The three generations of cephalosporins are used as examples here to delineate differences in potency, pharmacokinetics, efficacy, and potential for causing adverse reactions during the ideal formulary evaluation process.