[The pharmacoeconomics of treatment of severe infections in intensive care].

Pharmacoeconomics play an increasing role in rational decision-making for public health and therapeutic strategies. Relevant concepts such as benefit, efficacy, efficiency and utility have to be clearly defined. Fractionating the hospital costs implies to separate direct (medical and nonmedical), indirect and intangible costs, fixed and variable costs. The costs of side-effects, biological tests, administration of the drug and therapeutic failures have to be taken into account. From the medical point of view, the main pharmacoeconomic criterium is the cost/efficacy ratio, not the acquisition costs of the drug. Examples of the translation of these concepts to antibiotherapy in the intensive care unit are given, with analysis according to the principles of evidence-based medicine.