DRUG VEHICLE BASED APPROACHES OF PENETRATION ENHANCEMENT

Transdermal delivery of drugs through the skin to the systemic circulation provides a convenient route of administration for a variety of clinical indications. For transdermal delivery of drugs, stratum corneum is the main barrier layer for permeation of drug. So to circumvent the stratum corneum and to increase the flux through skin membrane, different approaches of penetration enhancement are used. Many reviews had described regarding the chemical penetration enhancement but vehicle based enhancement approach is not exploited for reviews. Drug-vehicle based enhancement methods such as drug selection, vesicles and particles, liposomes, prodrugs and ion-pairs, chemical potential of drug, eutectic systems, complexation are used in transdermal research as better alternative method to enhance permeation of drugs through skin. The review presents mainly the routes of penetration through skin and the approaches of drug-vehicle interaction based enhancement to optimise the transdermal delivery system.