Do the weight differences between individual prednisone or salicylic acid calibrator tablets affect the dissolution results?
A The calibration using these tablets typically does not produce results representing 100 % dissolution. Salicylic Acid tablets are non-disintegrating and the dissolution rate is dependent on the surface area exposed. The disintegrating prednisone tablets dissolution rate depends on how fast the surface of the drug particles is exposed to the medium. It is our understanding that neither of these tablets will give different results based on the small differences that may be seen in either drug loading or tablet weight. As part of the initial evaluation of a new lot of calibrator tablets,the USP laboratory evaluates the assay value and the uniformity of individual tablets. Typically the variability in salicylic acid tablet mass is approximately 2% RSD. The variability of prednisone content in a recent lot of disintegrating calibrator tablets was also about 2 % RSD.
