[Metabolism of drugs in the skin]

The principle metabolic pathways in the skin and their practical implications are still largely unknown. Some insight has already been gained from a few in vivo methods (application of radiolabelled substances in animal and man) and several in vitro methods (skin slice models, use of skin homogenates, skin perfusion models). Most of the drugs investigated with these methods have been glucocorticosteroids: cortisol (oxidation to cortisone, reduction at C-20 and delta 4), diflucortolonvalerate, fluocortinbutylester (ester cleavage). Estradiol (oxidation to estrone) and vidarabine-5-valerate (ester cleavage) are drugs of a different type that have been examined.