Liquorice (Glycyrrhiza glabra) in Floating Drug Delivery Systems: Innovations in Herbal Gastroretentive Therapy for Peptic Ulcer

The peptic ulcer patients pose a problem to the global healthcare since the oral treatment regimens such as fast gastric emptying and unpredictable drug in vivo absorption have been restricted. Floating Drug Delivery System (FDDS) has entered the scene as an effective technique of enhancing the gastric retention, long aging effect of drugs as well as enhancement of therapeutic effects. Liquorice (Glycyrrhiza glabra) is a well-characterised medicinal plant which is typified by a well-defined phytochemical profile of constituent compounds namely glycyrrhizin, liquiritigenin and flavonoids that are related to its anti-inflammatory, antioxidative, mucoprotective, and anti-Helicobacter pylori phenomenon. Different new approaches have addressed integration of liquorice in FDDS through mucoadhesive microspheres, guar gum based hydrogels, deglycyrrhizinated liquorice gastroretentive systems and excellent solubility of their spray-dried extracts. Improvements made in the liquorice loaded nanoparticles and core shell nanohybrids also in the area of nanotechnology further increased the bioavailability and site specific delivery. Greater synergy potential of therapeutic action also exists in polyherbal FDDS formulations that will contain liquorice and modern polymers. Despite promising preclinical data, not all barriers to implementing a liquorice-based FDDS in a clinical situation have been overcome, including potential stability issues, the harmonisation of herbal actives, regulatory challenges and the challenges of cost-effectiveness in the large scale manufacture. Translation will be done in the market to fill out these gaps with stringent writing on formulation optimization, in vivo studies as well as optimally planned clinical trials. This review will collate the current body of knowledge of liquorice against the background of demonstrating the treatment potential of liquorice as well as the developments that could be the tipping point in the application of liquorice to the treatment of gastroretentive ulcers in the future.