Effect of Certain Tablet Formulation Factors on Dissolution Rate of the Active Ingredient I11

Abstract

A hydrophobic tablet lubricant (magnesium stearate) has been found to retard the dissolution of salicylic acid from model compressed tablets, while a water‐soluble, surface‐active lubricant (sodium lauryl sulfate) enhanced markedly the dissolution rate. Experiments with nondisintegrating disks indicate that the more commonly used hydrophobic lubricants (magnesium stearate, aluminum stearate, stearic acid, talc) decrease the effective drug‐solvent interfacial area and thereby decrease the rate of dissolution of the drug, while water‐soluble lubricants (sodium oleate, sodium lauryl sulfate) do not have this effect. The dissolution rate enhancing effect of sodium lauryl sulfate (in the case of conventional tablets) is not due to any modification of microenvironmental pH or solubilization by micelles, but rather to the better penetration of solvent into tablets and their component granules and the resulting greater availability of drug surface.