Taste-masking assessment of solid oral dosage forms--a critical review

Approaches to improve the taste of oral dosage forms that contain unpleasant tasting drugs are versatile. Likewise, the analytical in vitro and in vivo methods to assess taste-masking efficacy are diverse. Taste-masking has gained in importance since the EU legislation on medicines for children came into force in 2007, and taste-masking attributes are often required by regulatory authorities. However, standardized guidance for the analytical evaluation is still poor. Published protocols rarely consider real conditions, such as the volume of saliva or the residence time of solid oral dosage forms in the mouth. Methodological limitations and problems regarding time point of evaluation, sampling or sample pretreatment are hardly ever addressed. This critical review aims to evaluate and discuss published strategies in this context.