Design and evaluation of sustained-release and buccal adhesive propranolol hydrochloride tablets

Abstract

The release of propranolol hydrochloride incorporated into sustained-release and buccal adhesive tablets was studied in vitro. The formulation containing 20% hydroxypropyl methylcellulose (HPMC) yielded good sustained-release matrix tablets. Buccal adhesive controlled-release tablets were prepared by compression of HPMC with polycarbophil (PAA), which served as the bioactive adhesive compound. The release behaviour of buccal adhesive tablets was found to be non-Fickian. The adhesion force was significantly affected by the mixing ratio of HPMC and PAA in the tablet and the weakest adhesion force was observed at the ratio of 1:1 (HPMC:PAA). Interpolymer complex formation was confirmed between HPMC and PAA in acidic medium by turbidity, viscosity and FT-IR measurements. The kinetics of sustained-release and buccal adhesive tablets of propranolol were examined in nine healthy volunteers. Conventional propranolol (Dideral®) was also studied for comparison purposes. As compared to conventional propranolol (40 mg), a single dose of 20% HPMC (160 mg) produced a smoother plasma level profile, with lower and delayed peak times. Dose corrected AUC 0–8 values were greater after Dideral® than after 20% HPMC (168.7 ± 80.3 vs 97.3 ± 36.1 ng h ml −1 p < 0.05). The buccal delivery of propranolol caused ulceration and serious irritation that took weeks to heal. There was no significant difference ( p > 0.05) in the AUC 0–4 values between 20% HPMC and buccal adhesive tablets.