AIM To prepare buspirone hydrochloride buccal adhesive tablet and investigate factors that influence drug release behavior and the drug release mechanism. METHODS Buspirone hydrochloride buccal adhesive tablet was prepared with double layers structure composed of drug core and adhesive layer. The materials of the drug core were carbopol 974 and lactose, the adhesive layers were carbopol 974 and HPMC K 4M . The influence of drug release factors such as adhesive layer component, adhesive layer weight and adhesive tablet hardness was investigated. The relationship between adhesive layer weight and drug release mechanism in vitro was studied. RESULTS The results showed that the weight of the adhesive layer and the hardness of adhesive tablet showed significant effects on drug release, but the adhesive layer component showed no significant effect. The optimum prescription of buspirone hydrochloride buccal adhesive tablet was carbopol∶HPMC=1∶1, adhesive layer weight=50%, and adhesive tablet hardness=4 kg. The study of drug release mechanism from adhesive tablet showed that it was double directions when adhesive layer weight was 20%, and single direction first then double directions when 33 33%, and single direction all along when 50%. CONCLUSION The speed and direction of drug release from adhesive tablet can be controlled by regulating adhesive layer weight.
