Transdermal preparations containing hydrophoic non-steroidal anti-inflammatory drugs
Disclosed is a transdermal preparation containing a hydrophobic drug. As a method of continuing the high drug permeation, it is used an unique hydrophilic polymer system in which the drug can be contained in a high concentration under no water environment, a solubility of the hydrophobic drug is decreased as the water is introduced to the patch from the skin, so that the drug is maintained at the saturation concentration even though the drug content is decreased as the drug is permeated to the skin. During the application of the transdermal preparation to the skin, it is possible to continuously permeate the high amount of drug, to maintain the sufficient adhesion during the use and to minimize the skin side effect, because the hydrophilic polymer absorbs the water from the skin. The hydrophilic polymer system can serve the function thereof through the hydrophobic adhesive layer capable of preventing the water quickly absorbed from the skin from being evaporated to the outside of the patch.
1. A transdermal preparation of a layered structure for a non-steroidal anti-inflammatory drug comprising:
a backing layer ( 1 ) located at the highest part of the layered structure and having a flexibility;
a hydrophobic adhesive layer ( 2 ) placed below the backing layer; and
a drug adhesive layer ( 3 ) placed below the hydrophobic adhesive layer,
wherein the hydrophobic adhesive layer ( 2 ) is free of the drug and contains a hydrophobic adhesive to prevent water absorbed from skin from being lost and the drug contained in the drug adhesive layer ( 3 ) from being reverse-transferred to the backing layer ( 1 ),
wherein the hydrophobic adhesive is selected from a group consisting of a polyisobutylene adhesive, a styrene-isoprene-styrene adhesive and a styrene-butadiene-styrene adhesive,
wherein the drug adhesive layer ( 3 ) contains the non-steroidal anti-inflammatory drug, an acrylic adhesives for adhering the transdermal preparation to the skin and a hydrophilic polymer resin for promoting the water absorption from the skin,
wherein the hydrophilic polymer resin is polyvinyl pyrrolidone or polyethyleneglycol, the total drug adhesive layer comprising 0.2-6 wt % polyvinyl pyrrolidone when the hydrophilic polymer resin is polyvinyl pyrrolidone, or 1-8 wt % polyethyleneglycol when the hydrophilic polymer resin is polyethyleneglycol, and
wherein the non-steroidal anti-inflammatory drug is one or more selected from a group consisting of ketoprofen, diclofenac, flurbiprofen and felbinac.
2. The transdermal preparation according to claim 1 , further comprising a release layer ( 4 ) placed below the drug adhesive layer, protecting the drug adhesive layer until the transdermal preparation is used and released when the preparation is used.
3. The transdermal preparation according to claim 1 , wherein the hydrophobic adhesive layer has a thickness of 40-100 μm.
4. The transdermal preparation according to claim 1 , wherein the non-steroidal anti-inflammatory drug of the drug adhesive layer is contained in an amount of 10-40 wt % for a total drug adhesive layer.
5. The transdermal preparation according to claim 1 , wherein the polyvinyl pyrrolidone has a molecular weight of 1,000-50,000.
6. The transdermal preparation according to claim 1 , wherein the polyethyleneglycol has a molecular weight of 400-8,000.
7. The transdermal preparation according to claim 1 , wherein the hydrophilic polymer resin of the drug adhesive layer is contained in an amount of 10 wt % or less for a total drug adhesive layer.
8. The transdermal preparation according to claim 1 , wherein the acrylic adhesives of the drug adhesive layer are contained in an amount of 40-80 wt % for a total drug adhesive layer.
9. The transdermal preparation according to claim 1 , wherein the drug adhesive layer further comprises a permeation enhancer for enhancing the drug permeation, and
wherein the permeation enhancer is a long chain fatty acid having a carbon number of 10-18 and derivatives thereof which are used in an individual or mixture form,
the fatty acid derivative being selected from a group consisting of lauryl alcohol, oleyl alcohol, sorbitan monolaurate, polyethyleneglycol monolaurate, propyleneglycol monolaurate, glycerin monolaurate, caprylic monolaurate and isopropyl myristate, and
the permeation enhancer is contained in an amount of 3˜20 wt % for a total drug adhesive layer.
10. The transdermal preparation according to claim 1 , wherein the backing layer is made of a woven or non-woven fabric having a unidirectional or dual directional flexibility, and wherein the woven fabric consists of a polyester based resin, urethane based resin or cotton, and the non-woven fabric consists of the polyester based resin or urethane based resin.