Penetration enhancers transdermal drug delivery

Cevc G. Transfersomes, liposomes and other lipid suspensions on the skin permeation enhancement, vesicle penetration, and transdermal drug delivery. Crit Rev Ther Drug... 

Walters, K.A. (1989). Penetration enhancers and their use in transdermal therapeutic systems. In Transdermal Drug Delivery — Development Issues and Research Initiatives, J. Hadgraft and R.H. Guy, eds. Marcel Dekker, New York, 197-246. 

The lack of significant impact of CPEs on transdermal delivery vehicles is related to the inherent nonspecific activity of CPEs in the different strata of the skin, as discussed earlier. This limitation may be overcome by utilization of mixtures of CPEs. Research has already shown that binary mixtures of CPEs provide increased permeation enhancement as well as increased safety compared to single enhancers. Such unique chemical combinations, called synergistic combinations of penetration enhancers or SCOPE formulations, offer new opportunities in transdermal drug delivery (46). 

Weichers J. Use of chemical penetration enhancers in transdermal drug delivery—possibilities and difficulties. Acta Pharmeceutica Nordica 1992 4 123-123. 

Jain A, Panchagnula R. Combination of penetration enhancers for transdermal drug delivery—studies with imipramine hydrochloride. Pharmazeutische Industrie 2004 66 478-482. 

Kanikkannan N, Kandimalla K, Lamba S, Singh M. Structure-activity relationship of chemical penetration enhancers in transdermal drug delivery. Curr Med Chem 2000 7 593-608. 

The list of materials that have been used as penetration enhancers as discussed above is not exhaustive but is intended to illustrate the range of agents that have been employed for facilitating transdermal drug delivery. Several common themes emerge from these considerations ... 

Wiechers, J.W., and R.A. de Zeeuw. 1990. Transdermal drug delivery Efficacy and potential applications of the penetration enhancer azone. Drug Design Del 6 87. 

Karande, P., et al. 2005. Design principles of chemical penetration enhancers for transdermal drug delivery. PNAS 102 4688. 

A description of transdermal drug delivery has been produced which is based on the physicochemical properties of the permeant. At this time transdermal delivery is limited to the administration of potent drugs. Higher doses may be accessible if penetration enhancers are incorporated into the formulation. The kinetic model shows what properties these should have and that they are a function of the physico-chemical properties of the drug. Various loss processes, e.g. microbial biotransformation, skin enzyme metabolism can be identified but cannot, as yet, be quantified. 

Surfactants—traditionally common constituents and stabilizers of topical vehicles, ranging from hydro-phobic agents such as oleic acid to hydrophilic sodium lauryl sulphate— have been tested as penetration enhancers to improve transdermal drug delivery. 

Terpenes such as o-limonene have been used as penetration enhancers (also called sorption promoters or accelerants) for improving transdermal drug delivery and work by penetrating into skin to reversibly decrease the barrier resistance. 

Benson, H.A.E. (2005) Transdermal drug delivery Penetration enhancement techniques. Curr. DrugDeliv., 2, 23-33. 

Because of the very extensive barrier properties of the stratum corneum, it is often necessary to increase the intrinsic rate of dermal or transdermal drug delivery to achieve the required therapeutic drug levels. In these instances, skin penetration and permeation enhancement... 

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