A polymer matrix system for transdermal delivery of Atenolol was developed for its prolonged and controlled release systemic availability. To achieve the desired and controlled release rate, different combinations of Eudragit RL with polyvinyl pyrrolidone and polyethylene glycol 4000 were used in the preparations of polymeric matrix system. These preparations were evaluated for in vitro release and permeation of the drug across pig skin. The desired systems exhibited linear relationship between drug release (Q) versus ne0.8(hr0.8). The product exhibiting required skin permeation 64 mcg/h/cm2 to achieve an effective plasma concentration was selected for the in vivo performance evaluation. The drug plasma profile was compared with the plasma profile obtained following the administration of a conventional oral dose of Atenolol. The study revealed that the designed polymeric matrix transdermal drug delivery system of Atenolol could be successful with improved performance.

Bilayer tablets are the advanced form of conventional immediate release tablet system, which consist of either two similar or different drugs combined in a single dose for effective treatment of the disease improving patient compliance. However, the multilayer tablet technology is demanding It also necessitates meticulous selection of excipients and manufacturing conditions for each technological stage. The aim of this review is to provide an outline of state of art of bilayer tablet technology and emphasise the difficulties experienced during Bilayer tablet manufacturing along with its  intend solutions for these challenges. Keyword: Bilayer tablet, Conventional release, Challenges encountered, Compliance.

A polymer matrix system for transdermal delivery of atenolol was developed for its prolonged and controlled release using different ratios of ethylcellulose and hydroxypropyl methylcellulose. These polymeric matrix films were characterized for thickness, tensile strength, moisture content and drug content. They were also studied for in vitro drug release and in vitro drug skin permeation. The drug release from the films was found to be Fickian diffusion type and exhibiting linear relationship between drug release (Q) vs. square root of time (t0.5). The in vitro skin permeation of drug from transdermal drug delivery system (TDDS) was evaluated using dermatomed pig skin. The product which shows in vitro drug skin permeation near to 64 mcg/h/ml was selected for in vivo studies. The in vivo studies revealed that Ma EC HPMC 46 is most effective among the other polymeric matrix TDDS. The AUC0-28 with Ma EC HPMC 46 was better than orally administered conventional doses at twelve hours interval (AUC0-28 1587 ng h/ml) as well as no trough and peaks in drug plasma level was recorded with TDDS. Hence, it could be concluded that the designed polymeric matrix TDDS of atenolol could be used successfully for effective and prolonged delivery of atenolol. However, it further demands exploration in clinic, an insight vision towards the development of TDDS for commercial use.

The buccal region within the mucosal cavity of the mouth provides an alternative route over an oral drug administration for systemic as well as local drug delivery. As the buccal mucosa has an abundant blood supply and is relatively permeable, it can be considered as most accessible and desired location for both local and systemic drug delivery. The buccal method for medication delivery greatly helps in avoiding issues in the gastrointestinal environment, such as increased first-pass metabolism and medication degradation. Bucco-adhesive systems offer varieties of advantages such as convenience in administration and termination of therapy in case of emergency, higher patient compliance, better bioavailability, rapid absorption, etc. This current review highlights the bucco-adhesive drug delivery system, its advantages and limitations, mechanisms and theories of mucoadhesion, different bucco-adhesive dosage forms, and bioadhesive polymers. It also highlights the current status on mucoadhesive drug delivery methods for the buccal cavity or bucco-adhesive systems. Keywords: Bioadhesion, mucoadhesion, bucco-adhesive drug delivery system, oral mucosa, first-pass metabolism, bioadhesive polymers.