Eprazinone (50-200 mg/kg; oral gavage; daily; for 4 days; adult male rats) at a dose of 200 mg/kg significantly increases total and individual (with the exception of phosphatidylinositol) phospholipid levels and decreases total neutral lipids. Lower doses of Eprazinone significantly decrease neutral lipid levels without affecting the phospholipids. In airway epithelial studies, mucosal addition of Eprazinone produces a dose-dependent partially reversible decrease in short-circuit current (Isc). The decrease in Isc at lower Eprazinone concentrations is accounted for entirely by a decrease in net chloride secretion while at higher concentrations both sodium and chloride transport are affected.