Structural and in vitro in vivo evaluation for taste masking.

Introduction: Although many techniques, such as complexation and microencapsulation, are used to mask the unpleasant taste of drugs, the success of all masking processes is evaluated in the same way. To evaluate the success of a masking process, a masked formulation must pass two tests: a structural test and an in vitro in vivo test. Areas covered: This review article highlights structural evaluation and in vitro in vivo evaluation of a taste-masking process. The structural evaluation has two criteria: the absence of any chemical interaction between the drug and the masking agent and the molecular distribution of drug in the network of masking agent. The in vitro in vivo section can be verified by electronic tongues, dissolution test, and volunteers and it should confirm that the final product, after applying the masking process, will have a lower rank in terms of taste. Expert opinion: This critical review helps researchers and industrial partners to evaluate a taste-masking process in a systematic way, leading to better understanding of taste-masking process and consequently improving the efficiency of masked dosage forms while hindering the unpleasant taste of drugs. This will ultimately improve the quality of life of many patients.