Background: Metoprolol succinate, a cardioselective β1-adrenergic receptor antagonist, exhibits suboptimal bioavailability due to its short gastric residence time and preferential absorption in the upper gastrointestinal tract. This study aimed to develop and evaluate gastro-retentive extended-release tablets of metoprolol succinate using hydroxypropyl methylcellulose (HPMC) as the primary matrix-forming polymer to enhance therapeutic efficacy and patient compliance.

Methods: Seven formulations (F1-F7) were developed using wet granulation technique with varying concentrations of HPMC (100-170 mg), sodium bicarbonate (80-150 mg), and microcrystalline cellulose as primary excipients. Comprehensive pre-formulation studies included organoleptic evaluation, melting point determination, solubility profiling, and Fourier transform infrared spectroscopy for drug-excipient compatibility assessment. Post-compression parameters including hardness, friability, weight variation, and thickness were evaluated according to pharmacopoeial standards.

Results: The optimized formulation F4, containing 170 mg HPMC and 90 mg sodium bicarbonate, demonstrated superior physical characteristics with hardness of 6.0 kg/cm², friability of 0.25%, and sustained drug release achieving 98% cumulative release over 12 hours. Pre-formulation studies confirmed excellent drug-excipient compatibility with melting point of 121-124°C and partition coefficient of 4.0, indicating favorable lipophilic characteristics for oral absorption.

Conclusion: The developed gastro-retentive tablets successfully provided controlled release of metoprolol succinate over an extended period, demonstrating potential for once-daily administration with enhanced patient compliance and therapeutic outcomes in cardiovascular disease management.

Keywords: Gastro-retentive, Metoprolol Succinate, Pharmaceutical