The influence of dose frequency and agent toxicity on the cost of parenteral antibiotic therapy.

The influence of the number of daily doses on the overall cost of antibiotic therapy is examined in a general surgery patient population. Patients receiving a single first-generation cephalosporin are compared with patients receiving two or three antibiotics (including an aminoglycoside) in terms of (1) the cost of the drug and the supplies, (2) time required for nursing and pharmacy personnel to prepare and administer the doses, and (3) the influence of agent toxicity (renal function) on physician-ordered laboratory tests. On the whole, combination therapy including an aminoglycoside was four times as expensive as single-agent (first-generation cephalosporin) therapy. If future studies demonstrate that single-agent antibiotic therapy is as effective as traditional combination therapy for specific infectious diseases, the influence of the number of daily doses of drug and agent toxicity may support the cost-effective use of the newer agents.