ABSTRACT:
Labetalol hydrochloride is an antihypertensive drug exhibiting extensive first-pass metabolism and a relatively short biological half-life, necessitating frequent dosing which may reduce patient compliance. The present investigation aimed to formulate and evaluate gastroretentive floating microspheres of labetalol hydrochloride to prolong gastric residence time and provide sustained drug release. Floating microspheres were prepared by the emulsion solvent diffusion method using ethyl cellulose and Eudragit RS100 as release-controlling polymers and polyvinyl alcohol as a surfactant. Preformulation studies confirmed the physicochemical suitability of the drug. FT-IR studies revealed no chemical interaction between the drug and polymers. The prepared microspheres were evaluated for flow properties, particle size, percentage yield, entrapment efficiency, in vitro buoyancy, and in vitro drug release. The microspheres exhibited good flow properties, high buoyancy (76–94%), and sustained drug release up to 12 hours. Among all formulations, F8 showed optimum characteristics with highest entrapment efficiency (97.2%), buoyancy (94%), and controlled drug release up to 12 hours. The study concludes that gastroretentive floating microspheres of labetalol hydrochloride can be an effective approach to enhance oral bioavailability and improve patient compliance.