Current status and the future of buccal drug delivery systems.

BACKGROUND The delivery of drugs through the buccal mucosa has received a great deal of attention over the last two decades, and yet there are not many buccal delivery products available on the market. OBJECTIVE This review outlines the advantages and disadvantages of buccal drug delivery, provides a historical perspective and discusses representative developmental and marketed drugs. METHODS The structure of the oral mucosa is briefly described to preface a description of the pathways for drug absorption and a critical discussion of permeation experiments. A brief historical perspective followed by a description of some of the currently marketed products provides a picture of where we are today. An indication is given of likely progress in this area and of the attributes of a successful business entity of the future. CONCLUSION The authors provide an assessment of the future potential of buccal and sublingual drugs.