A method for simultaneous quantitation of caffeine, ethoxybenzainide and propyphenazone is described. The method was based on reversed-phase high-pressure liquid chromatography with a mobile phase of methanoI-acetonitriIe-3% aqueous acetic acid solution (24 : 16 : 60, v/v). TTie compounds were well separated from each other by the propcedure, using salicylamide as internal standard. The method gave excellent results and provided a simple^ rapid ami accurate method for sep* aration and quantitation of synthetic mixtures and commercial products.