Influence of Intralipid infusion on the elimination of phenytoin.

On the ground of clinical observations the hypothesis was tested that a changed disposition of phenytoin could bring about a shortened half-life. In vitro it appeared that the amount of phenytoin bound to the Intralipid fraction was more than twice the amount present in the plasma fraction. In an in vivo rat model it was shown that the half-life of phenytoin was indeed influenced by Intralipid administration, but contrary to clinical observations phenytoin half-life was prolonged. Some possible explanations for this discrepancy are discussed.