The tabletting properties of Stearolac-S

The tabletting properties of STEAROLAC-S was evaluated in this study and compared to those of stearic acid and magnesium stearate in three direct compression tablet formulations. An instrumented rotary tabletpress was used to determine the unit ejection force of tablets made from the direct compression formulations. The effects of the excipients on tablet hardness, friability, disintegration and dissolution rate were also evaluated. Tablets containing 3 - 4 % w/w STEAROLAC-S gave unit ejection force values comparable to those of tablets containing 2% w/w magnesium stearate. Tablets containing 4% STEAROLAC-S exhibited better physical properties than those containing 2% magnesium stearate. Prolonged mixing improved the lubricating efficiency of STEAROLAC-S and had no deleterious effect onthe disintegration of hydrochlorothiazide and ascorbic acid tablets. STEAROLAC-S does not possess the lubricating ability of magnesium stearate but appears to be a useful candidate for the formulation of sustained release chlorpheniramine maleate and phenylpropanolamine hydrochloride tablets.