DefinePK

Abstract

Valproic acid is a widely prescribed antiepileptic drug known for its broad-spectrum efficacy, yet its conventional formulations are limited by a short half-life, fluctuating plasma levels, and frequent dosing requirements, all of which compromise therapeutic efficacy and patient compliance. To overcome these challenges, this study focuses on the formulation and evaluation of a dual-layer tablet comprising an immediate-release (IR) layer and a sustained-release (SR) layer. The IR layer facilitates rapid onset of action, while the SR layer ensures prolonged drug release, reducing dosing frequency and enhancing plasma concentration stability. Preformulation studies assessed drug-excipient compatibility using FTIR and DSC, while the final bi-layer tablets were evaluated for physicochemical properties, in vitro dissolution profiles, and comparative performance against marketed formulations. Results demonstrated that the optimized bi-layer formulation successfully achieved biphasic drug release, improved dissolution performance, and offered a promising approach for long-term valproic acid therapy. The formulation aligns with current pharmaceutical trends toward patient-centric, controlled-release dosage forms and represents a significant step forward in improving antiepileptic drug delivery.