Abstract
Over the past decades, polymeric-controlled drug delivery systems have been developed to deliver drugs into the body in an effort to overcome the disadvantages of frequency of administration and excess drug loading. The majority of research in controlled drug delivery has focused on systems where release rates follow the zero order. The release kinetics of active agents from the matrix not only depends on the devices, but also on the environment. Achievement of zero-order release kinetics with oral delivery systems is difficult. However, transdermal drug delivery systems (TDDS) are useful in achieving continuous and constant drug infusion [1].