Transdermal delivery of drugs

Singh J, Roberts M. Transdermal delivery of drugs by iontophoresis a review. Drug Delivery 1989 4 1-12. 

Chien Y, Behl C. Iontophoretic (transdermal) delivery of drugs overview of historical development. J Pharm Sci 1989 78 353-354. 

Kydonieus, A., and Berner, B. Transdermal Delivery of Drugs. Boca Raton, FL CRC Press, 1987. 

Kydonieus, A., Wille, J., and Murphy, G. Fundamental concepts in transdermal delivery of drugs, in Kydonieus, A., and Wille, J. (eds.), Biochemical Modulation of Skin Reactions Transdermals, Topicals, Cosmetics. Boca Raton, FL CRS Press, 2000, pp. 1-14. 

Transdermal Delivery Systems. Transdermal delivery of drugs over extended periods of time for systemic therapy has received significant attention. The importance and future prospects of this field are further reflected in the section on Transdermal and Transmucosal Delivery Systems (Chapters 17-23). Intact human skin, once thought to be an impermeable barrier, was realized as a potential portal of entry for systemic drug therapy only recently. 

Simulations representing these conditions are presented in Figures (7) and (8). Both PE1 and PE2 have similar effects on the transdermal delivery of drug D1 as compared with the control. They enhance delivery but PE2 has little advantage. However, in the case of D2, PE1 is ineffective in increasing drug delivery whereas PE2 has considerable effect. Thus the optimal effect that a penetration enhancer should have will be dependent on the physicochemical... 

Recently, for the transdermal delivery of drugs using carrier systems, attention has been focused on the development of transformable [284,285] or elastic vesicles [12], These vesicles are liposomes that contain surfactants or in general edge activators in addition to phospholipids in their lipid membranes (Figure 10), a fact that... 

Banga AK. Electrically assisted transdermal delivery of drugs. In Wise DL, ed. Handbook of Pharmaceutical Controlled Release Technology. New York, Basel Marcel Dekker, 2000, pp. 567-581. 

Studies were performed in vivo on two volunteers as well as in vitro using porcine skin. Although not directly related to tablet evaluation, the work is notable for its contribution to the transdermal delivery of drugs, potential NIR prediction of drug penetration through the skin, and conclusions regarding moisturizer use on the skin. 

Jamstrom, R. Hirvonen, J. Composition for Transdermal Delivery of Drugs. US Patent 6,254,883, July 3, 2001. 

Phillips, C.A. Michniak, B.B. Transdermal delivery of drugs with differing lipophilicities using azone analogs as dermal penetration enhancers. J.Pharm.ScL, 1995, 84, 1427-1433... 

Many chemicals are more soluble in lipids than in water. The lipid layer of the stratum corneum will dissolve and can absorb chemicals placed on the surface of the skin. In fact, this characteristic is important in transdermal delivery of drugs, for example, the skin patch for drug delivery, and in what has been termed substantivity or persistence of the applied antimicrobial. 

Transdermal delivery of drugs for systemic absorption is often more convenient than the oral route, since drugs avoid the the liver metabolism thus requiring lower doses and less potential for side effects. 

Bramwell BE, Williams LA. The use of Pluronic lecithin organogels in the transdermal delivery of drugs. IntJ Pharm Compd. 16(1) (2012) 62-63. 

Kydonieus, Agis F. Transdermal Delivery of Drugs, Bemer, B., Ed. CRC Press Boca Raton, FL, 1987, Vol. L... 

The essentially polar nature of commonly used ILs, however, limits their applications in areas that necessitate the use of certain nonpolar solutes. For example, while ILs have emerged as promising media for performing chemical reactions that require a water-free environment like Diels-Alder reaction, esterification, and polymerization, their applications are sometimes limited due to the poor solvation of nonpolar reactants and products [29]. Likewise, while ILs are known to solubilize several important drugs that are sparingly soluble in water, transdermal delivery of drug-IL formulations is limited by the hydrophobic barriers of the skin against polar ILs [30,31]. 

The stratum comeum basically contains a mixture of cholesterol, free fatty acids, and ceramides, placed in multilayers. They mediate both the epidermal permeability barrier and the transdermal delivery of both lipophilic and hydrophilic molecules. Smdies have shown that each of the three key lipid classes is required for normal barrier function (37). These reports also show the potential of certain inhibitors of lipid synthesis to enhance the transdermal delivery of drugs like lidocaine or caffeine. Thus, the modulation of stratum cor-neum lipids is an important determinant of the barrier permeability to both hydrophobic and hydrophilic compounds transport and drag penetration. It has been reported that an inverse correlation exists between solute penetration and stratum comeum hpid content (38). 

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