The granulation of ternary mixtures containing lactose and boric acid with different starches.

Ternary mixtures of lactose, boric acid and starch have been granulated by massing and screening. The properties of the granules have been compared with those resulting from granulation of blends of lactose and boric acid without starch. Potato, maize and rice starches have been studied as the third component at concentrations similar to those employed in tablet formulations. The starches caused a reduction in both mean granule size and granule strength. The effect is dependent on the proportions of the excipients. Increasing the amount of binder solution used gave bigger, stronger granules but did not compensate for the effects produced by the starches.