Background: Atenolol, a cardioselective β₁-adrenergic blocker widely used in hypertension management, suffers from poor bioavailability (~50%) and short elimination half-life (6-7 hours) due to its narrow absorption window in the upper gastrointestinal tract. Conventional formulations require frequent dosing, leading to poor patient compliance.

Objective: To develop and evaluate gastroretentive floating tablets of atenolol using hydrophilic polymers to enhance gastric residence time, improve bioavailability, and achieve sustained drug release for improved hypertension management.

Methods: Six floating tablet formulations (F1-F6) containing 50 mg atenolol were prepared using wet granulation technique with varying concentrations of hydroxypropyl methylcellulose (HPMC 15cps, 60-90 mg), chitosan (25-60 mg), and guar gum (50-60 mg). Comprehensive preformulation studies included organoleptic evaluation, solubility analysis, and compatibility assessment. Tablets were evaluated for physical parameters (weight variation, hardness, friability, thickness), floating characteristics (lag time, total floating time), content uniformity, and in vitro dissolution over 12 hours in 0.1N HCl using USP apparatus II.

Results: All formulations demonstrated acceptable physical properties with weight variation within ±7.5%, hardness 2-3 kg/cm², friability 0.5%, and content uniformity 99.72±0.83%. Floating lag time was 5.2±0.3 minutes with total floating time exceeding 12 hours. In vitro dissolution studies revealed sustained drug release with F2 achieving optimal performance, releasing 98.1% drug over 12 hours. Flow properties indicated fair to good characteristics with bulk density 0.50 g/mL, tapped density 0.625 g/mL, angle of repose 29.2°, compressibility index 20%, and Hausner ratio 1.25.

Conclusion: Gastroretentive floating tablets of atenolol were successfully developed with F2 formulation demonstrating superior sustained release characteristics, prolonged gastric retention, and potential for improved bioavailability. This approach offers a promising strategy for enhanced hypertension management through reduced dosing frequency and improved patient compliance.

Keywords: Atenolol, Floating Tablets, Gastroretentive Drug Delivery, Hypertension, Sustained Release, Bioavailability Enhancement.