Transdermal penetrants hormone

On the other hand, highly lipophilic compounds, such as hormones, can be solubilized via the prodrug approach. For example, the rate of transdermal absorption of the highly lipophilic drug, testosterone, was enhanced over 50-fold by forming water-soluble, yet lipophilic, prodrug ester.f The prodrug testoster-onyl-4-dimethylaminobutyrate was found to penetrate human skin tissue, in vitro, 54 times faster than... 

Research into new peptide hormone pharmaceuticals continues along several lines. Probably the most active area of research is into alternative delivery methods such as oral, nasal, buccal, transdermal, or pulmonary. All of these alternatives share issues of barrier penetration (whether mucosal or epidermal), protein stability, rate of clearance, and bioavailability. 

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