Plant-Based Excipients in Modern Pharmaceutical Formulations: Recent Advances, Regulatory Challenges, and Future Perspectives

Abstract

Excipients are essential components of pharmaceutical formulations that improve drug stability, bioavailability, manufacturability, and patient acceptability. Traditionally, synthetic and semi-synthetic excipients have been widely used; however, growing concerns about toxicity, environmental sustainability, and patient safety have spurred interest in plant-derived excipients. Plant-based excipients obtained from natural sources such as gums, mucilages, starches, cellulose derivatives, and other phytopolymers possess excellent biodegradability, biocompatibility, low toxicity, and multifunctional properties. Recent advancements in pharmaceutical technology have expanded the use of plant-based excipients in both conventional dosage forms and novel drug delivery systems, including nanoparticles, microspheres, hydrogels, transdermal systems, and 3D-printed medicines. Natural polymers such as alginate, pectin, chitosan, starch, and cellulose derivatives have demonstrated significant potential in controlled release, targeted delivery, and improved therapeutic performance. Despite their advantages, challenges related to standardization, batch-to-batch variation, purity, stability, and regulatory acceptance limit their widespread industrial application. Advanced extraction methods, characterization techniques, and regulatory harmonization are required to overcome these limitations. This review discusses the classification, recent advances, pharmaceutical applications, regulatory challenges, and future perspectives of plant-based excipients in modern pharmaceutical formulations.