Drug absorption through skin

Noven/DOT Matrix Alza/D-Trans delivery/ absorption through skin drug/formulation from environmental aggrevates Clear barrier offers aesthetics Pouching as primary/ secondary package Barrier property on carrier web critical Chemical inertness... 

Generally, drug absorption through the skin is slow absorption can be increased by occlusive dressing... 

Billich A, Aschauer H, Aszodi A, Stuetz A. (2004) Percutaneous absorption of drugs used in atopic eczema Pimecrolimus permeates less through skin than corticosteroids and tacrolimus. Int J Pharm 269 29-35. 

Methylsalicylic acid, unlike acetylsalicylic acid, is nearly exclusively used as an external rubifacient drug for painful muscles or joints and distributed as ointments or liniments due to their irritating effects on the gastrointestinal mucosa. Absorption through intact skin is possible and has led to prosecution following detection in race-horse urine. 

This approach consists of transiently increasing the permeability characteristics of the cornea by appropriate substances, known as penetration enhancers or absorption promoters. It bears a strict analogy to techniques aimed at facilitating drug penetration through the skin and other epithelia such as the buccal, nasal, intestinal, or rectal. 

Hewitt, G.G., J. Perkins and S.A.M. Hotchkiss (2000). Metabolism of fluroxypyr, fluroxypyr methyl ester, and the herbicide fluroxypyr methylheptyl ester. I. During percutaneous absorption through fresh rat and human skin in vitro. Drug Metabol Disp., 28, 748-754. 

Up to 40% of topically applied clioquinol can be absorbed percutaneously in man (20). Formulations that contain clioquinol are often used to treat diaper rash in a child of 10 kg treated with 1 g of clioquinol 3% tds, the amount of drug applied would be 9 mg/kg/day. However, it is possible that in infants with diaper rashes the actual absorption of the drug would be over 40%, since absorption through inflamed skin occurs more readily than through intact skin, and infant skin is more permeable than adult skin (21). 

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