Nicotine patches have been the king of the nicotine replacement therapy (NRT) castle for over a decade. While “the patch” is now a common household term for the drug, many do not know how these devices actually get nicotine into a quitter’s system. So, how do nicotine patches work?
The first place to look when answering this question is their design. There are two types of nicotine patches; they differ in how they control how much nicotine enters the bloodstream. The first is a membrane controlled patch. As the name suggests, there is a membrane, or a porous barrier, that lets only a limited amount of the nicotine through. The second type is a matrix controlled patch which work with your skin’s saturation rate.
The membrane controlled patch is made up of several layers of material. The first is the outer backing layer protective layer which keeps the concentrated nicotine inside the patch. The second layer is the drug reservoir, which are where the nicotine is stored as well as other chemicals that encourage the body to absorb the drug. Then there is the rate-controlling membrane which controls how much nicotine is allowed through. Finally there is an adhesive layer that sticks to the skin and serves as a vehicle to get nicotine to it.
The matrix controlled patch only has two layers, the outer backing layer and the adhesive. The top protective layer is similar to the membrane controlled patch, but they differ in that the nicotine is embedded right in the adhesive layer. The rate of delivery of the nicotine is based on how saturated the skin is, and the matrix controls this saturation.
The nicotine contained in these two types of patches is slowly released and absorbed through the pores in the skin and enters the blood. When it reaches the bloodstream it is quickly carried to the brain where it attaches to the same receptors.
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Nicotine Transdermal System