Molecular transdermal transport system

#Transdermal drug delivery offers many advantages over other types of drug delivery. With transdermal delivery, a localized delivery of drug molecules can be achieved, which makes transdermal drug delivery target specific. Further, transdermal drug delivery avoids the gastro intestinal complications caused by oral delivery. While transdermal drug delivery offers these and other advantages, a system than can quickly and reliably deliver predictable quantities of drug molecules through the skin has heretofore not been developed.

#The evolution of transdermal drug delivery has centered around patch technology. Patch technology is based on the ability to hold an active ingredient in constant contact with the epidermis. Over substantial periods of time, drug molecules, held in such a state, will eventually find their way into the bloodstream. Thus, patch technology relies on the ability of the human body to pick up drug molecules through the skin. Transdermal drug delivery using patch technology has recently been applied for delivery of nicotine, in an effort to assist smokers in quitting, the delivery of nitroglycerine to angina sufferers, the delivery of replacement hormones in post menopausal women, etc. These conventional drug delivery systems comprise a patch with an active ingredient such as a drug incorporated therein, the patch also including an adhesive for attachment to the skin so as to place the active ingredient in close proximity to the skin.

#Problems with patch technology abound. First, active drug molecules have a difficult time passing through the skin, as the skin poses a significant barrier. In fact, in order for a drug molecule to reach the bloodstream, it must pass through the epidermis, stratum corneum (an especially dense layer of cells), dermis and capillary cell structure. Second, real world conditions such as the patient's obesity, metabolism and circulatory efficiency can effectively prevent transdermal drug delivery from occurring. Third, patch technology can be used only for treatments involving extensively long treatment periods, since the flow rate of drug molecules is so small. Finally, patch adhesion to the skin causes extensive skin trauma as well as cosmetic problems. Specifically, most adhesives currently used tend to aggressively adhere to the skin so that their removal may cause irritation and trauma. Indeed, subsequent patches used by a given individual are often applied to a different area of the skin in order to minimize such irritation and trauma.

#Vegetable oil, papaveroline and the active ingredient are placed in a mixing vessel. The contents are then agitated therein to achieve a uniform blend. Xanthan gum is then added slowly with the mixing vessel contents being continually agitated. The agitation continues until a uniform blend is achieved. Other inactive ingredients may be added, and again the contents mixed until uniformity is achieved.

#The contents are removed from the mixing vessel and are applied directly to the skin at the desired transport site by gentle massaging for approximately 60 seconds or until the mixture disappears.