PERMEATION ENHANCERS COMPATIBLE WITH TRANSDERMAL DRUG DELIVERY SYSTEMS OVERCOMING THE SKIN BARRIER FUNCTIONS: CURRENT AND FUTURE PROSPECTS

Transdermal drug delivery system (TDDS) provides a leading edge over injectables and oral routes by increasing patient compliance and avoiding the first-pass metabolism respectively. Transdermal delivery not only provides controlled, constant administration of the drug, but also allows continuous input of drugs with short biological half-lives and eliminates pulsed entry into the systemic circulation, which often causes undesirable side effects. The oral route of transdermal drug delivery enables avoidance in gastrointestinal absorption. One of the greatest innovations of novel drug delivery in transdermal patch skin adhesion is the most important functional properties for a TDDS. Poor adhesion results in improper dosing of patients and potential accidental dosing of patients, who may pick up fallen patches. The adhesive of the TDDS is critical to the safety, efficacy, and quality of the product. Drug therapy may be terminated rapidly by the removal of the application from the surface of the skin. This article provides a framework for scientific work to improve transdermal adhesive performance and provides an overview of types of transdermal, their anatomy, and the role of adhesion, the possible adhesion failure modes and how adhesion can be measured. Topical administration of therapeutic agents offers many advantages over conventional oral and invasive methods of drug delivery. FDA reports on the lack of adhesion of transdermal system products are presented. Pros and cons of in-vitro techniques, such as peel adhesion, tack and shear strength in-vivo techniques used to evaluate adhesive properties are discussed.