Formulation and Evaluation of Buccal Films Containing Losartan Potassium for Antihypertensive Therapy

Losartan Potassium, an angiotensin II receptor blocker used in the treatment of hypertension, exhibits limited oral bioavailability due to extensive first-pass metabolism. The present study aimed to formulate and evaluate controlled-release mucoadhesive buccal films of Losartan Potassium using the solvent casting method to enhance bioavailability, provide sustained drug release, and improve patient compliance. The buccal films were prepared using Hydroxypropyl Methylcellulose E15 (HPMC E15), Gelzan CM, Sodium Alginate, Polyvinyl Alcohol (PVA), and Propylene Glycol as a plasticizer. The prepared films were evaluated for thickness, weight variation, folding endurance, surface pH, swelling index, drug content, and in vitro drug release. FTIR studies confirmed the compatibility of Losartan Potassium with the selected polymers, indicating the absence of significant drug–polymer interactions. The prepared films exhibited satisfactory physicochemical and mechanical properties, with thickness ranging from 0.123 to 0.170 mm, drug content ranging from 85.51% to 91.86%, and surface pH values close to the physiological pH of the buccal cavity. The optimized formulation (F6) showed the highest cumulative drug release of 91.83% over 8 hours, along with excellent folding endurance and satisfactory swelling behaviour. These findings indicate that the developed controlled-release mucoadhesive buccal films of Losartan Potassium are a promising alternative to conventional oral dosage forms for improving bioavailability, providing sustained antihypertensive therapy, and enhancing patient compliance.