Review of Floating Pulsatile Drug Delivery Systems: Formulation, Evaluation, and Chronotherapeutic Applications

The article is a comprehensive review of floating pulsatile drug delivery systems, focusing on their designprinciples, formulation strategies, evaluation parameters, and chronotherapeutic applications. It emphasizes howcombining gastro-retentive floating mechanisms with time-controlled pulsatile release can optimize drugtherapy in accordance with circadian rhythms, particularly for diseases showing time-dependent variation insymptoms. The review discusses the physiological challenges of oral delivery, classification and mechanisms offloating systems (effervescent and non-effervescent), major pulsatile designs (single-unit and multiple-unitsystems), and key evaluation tests such as micromeritic properties, tablet quality control, dissolution, andin-vitro buoyancy studies. It also highlights the role of chronobiology, chronopharmacology, and emergingtechnologies (e.g., solid lipid nanoparticles and advanced polymers) in improving site-specific, time-specificdelivery, enhancing bioavailability, reducing side effects, and improving patient compliance in chronotherapy.