Administration of lysine acetylsalicylate to anaesthetized rabbits induced a marked decrease in bile flow and biliary secretion rates of sodium, potassium, chloride and bicarbonate. Bile acid concentrations were increased but biliary bile acid outputs were similar to those observed in control animals after i.v. injection of saline or lysine. Our results confirm that different species have different susceptibilities to salicylates since in other species this group of drugs is choleretic. It is suggested that the cholestatic effect of acetylsalicylate in the rabbit is due to acetylsalicylate and that it is associated with a reduction in the bile acid-independent bile flow since bile acid outputs remained constant after administration of the drug.