Phenytoin and fosphenytoin: A model of cost and clinical outcomes

We developed a pharmacoeconomic model to compare costs and clinical outcome s of administering phenytoin and fosphenytoin alone and in combination in h ospitalized patients. Effectiveness data were obtained by distributing a qu estionnaire to 33 registered nurses at three acute care hospitals who worke d in critical care, neurology services, or emergency department. The questi onnaire addressed methods of phenytoin and fosphenytoin administration, fre quency of adverse reactions, methods of treating adverse reactions, and dem ographic information. The model estimated that if 50% of phenytoin loading doses were substituted with fosphenytoin, a reduction in adverse events res ulted in an estimated increase of $36/patient cost to the hospital. If phen ytoin maintenance dosages were substituted with fosphenytoin, the model pre dicted essentially no change in cost to the hospital. It appears that fosph enytoin reduces adverse events at a reasonable increase in total hospital c osts.