The effect of pentamidine salts on the NADPH-dependent oxidase of stimulated neutrophilic granulocytes.

Both pentamidine isethionate and pentamidine mesylate induced a depression in activity of the NADPH-dependent oxidase system of stimulated human neutrophilic granulocytes. This drug-induced effect occurred at concentrations of 0.7, 1.1 and 1.5 mg/l, values within the therapeutic range after parenteral administration of a standard dose of either pentamidine salt, and was dose-related. There was no significant difference between the two salts with regard to this suppression in neutrophilic granulocyte function. The reduced activity of the NADPH-dependent oxidase system, after incubation with pentamidine salts, may be associated with the previously observed depression in candidacidal capacity of human neutrophilic granulocytes treated with these drugs.