Evaluation, correction and masking methods for unpleasant tastes of drugs: A comprehensive review

The unpleasant tastes of drugs, including bitterness, pungency, astringency, and sourness, significantly impedes patient adherence, particularly among pediatric and geriatric populations. Accurate evaluation of these tastes is essential for optimizing formulations and improving drug quality during development. Developing effective taste correction and masking strategies has become a pivotal challenge in pharmaceutics, aiming to improve palatability by concealing unpleasant tastes or modulating sensory perception without compromising therapeutic efficacy. To address these challenges, a comprehensive understanding of current methodologies and innovative strategies is crucial for advancing patient-centric drug design. This review systematically summarizes evaluation methods, correction strategies, and masking techniques for drug-related unpleasant tastes, providing theoretical and technical insights for optimizing drug palatability. Initially, the physiological mechanisms underlying the four types of unpleasant drug tastes are described. Quantitative evaluation techniques, including sensory panels, chemical assays, biological assessments, electronic tongues and biosensors are systematically examined, with a particular emphasis on biosensors due to their remarkable sensitivity and biomimetic properties. Additionally, strategies to ameliorate palatability are elaborated. Taste correction involves the use of sweeteners, sour agents, and flavor enhancers, while taste masking employs physical barriers, chemical modifications, or biomaterial-based encapsulation to minimize drug-taste bud interactions. Subsequently, prospective avenues are suggested, highlighting the potential of interdisciplinary innovations such as artificial intelligence (AI)-driven predictive models and nanotechnology-based delivery systems. These advancements hold the promise of revolutionizing the precision and efficacy of taste evaluation and masking, ultimately propelling personalized drug development forward.