Influence of therapeutic concentrations of phenylbutazone on granulocyte function.

The influence of therapeutic concentrations of phenylbutazone on human granulocyte function has been examined using a method which facilitates a precise in vitro evaluation of the phagocytic and bactericidal activities of polymorphonuclear leucocytes. Phenylbutazone caused a marked reduction in intracellular killing of bacteria by the granulocytes. Whether this inhibition of granulocyte function also takes place in vivo resulting in enhanced susceptibility to infection, remains unknown.