ABSTRACT
Several different design approaches for transdermal patches have been developed. Transdermal product development has matured greatly. The liner materials should allow easy handling during all operations in the transdermal manufacturing process. The testing of transdermal drug delivery systems is both similar and unlike that of other pharmaceutical dosage forms. Although drug delivery is the primary objective of all transdermal dosage forms, the establishment and maintenance of skin adhesion is fundamental to all systems. The specific location of the drug within the system and the associated drug delivery formulation can be used to categorize a transdermal patch into one of the design configurations. The membrane plays a critical role in drug release and drug delivery in the reservoir-type design. However, this patch configuration is particularly vulnerable to dose dumping. Three types of pressure sensitive adhesives are commonly used in transdermal drug delivery systems: polyisobutylenes, silicones and acrylics.
