Claims for Patent: 5,741,510

Summary for Patent: 5,741,510

Title:	Adhesive patch for applying analgesic medication to the skin
Abstract:	A medication patch to be applied to the skin includes a self-supporting backing layer to give the patch the required integrity and strength by acting as a supporting framework for other components, and a flexible hydrophilic pressure-sensitive adhesive reservoir comprising a natural or synthetic polymer for the sustained release of medication to be absorbed topically through the skin into the body of a patient. The reservoir has two portions: first, an external coating layer with an exposed lower skin-contacting surface that forms a pressure-sensitive bond with the skin, and second, an upper internal portion which infiltrates the porous backing and becomes solidified therein after being applied so that the reservoir and the backing are unified, enabling the backing itself to act as a storage location for the medication-containing reservoir. The medication within the reservoir migrates over time from within the backing through the lower coating layer and passes through the skin to provide sustained release of the medication into the body of a patient.
Inventor(s):	Rolf; David (Minneapolis, MN), Sjoblom Urmann; Elisabeth K. (Tomahawk, WI)
Assignee:	Lectec Corporation (Minnetonka, MN)
Application Number:	08/629,191
Patent Claims:	1. A non-occlusive medication-containing analgesic adhesive patch for the transdermal delivery of medication into the body of a patient through the skin for the relief of pain including arthritis, backache, and muscular aches and strains comprising, a flexible pressure-sensitive adhesive hydrocolloidal gel matrix as a layer including: 1) a natural or synthetic polymer, 2) a biomedically active pain relieving substance dispersed in the gel matrix layer for being absorbed through the skin into the body of the patient, a flexible backing sheet for supporting the matrix, said backing sheet comprising a sheet of water insoluble material having an upper surface and a lower surface, said patch including both the backing and the matrix layer is non-occlusive with a moisture vapor transmission rate that is greater than that of a person's skin, said adhesive matrix layer is cured so as to solidify in contact with the backing, said adhesive patch having the following portions proceeding from a lower surface of the adhesive patch to said upper surface of the backing: a) a portion of said pressure-sensitive adhesive matrix layer located below the lower surface of the backing, said layer having an exposed pressure-sensitive adhesive surface for bonding the patch to the skin of the patient, b) an upper portion of the matrix bonded to the backing, c) the backing having a portion that is free of said matrix, d) the backing has an upper surface that is spaced apart from the matrix and said biomedically active substance is dispersed in the matrix such that the matrix releases the biomedically active substance into the body of the patient through said adhesive surface of the matrix that is bonded to the patient's skin. 2. The medication-containing adhesive patch of claim 1 wherein the polymer comprises a member selected from the group consisting of gum karaya, gum acacia, locust bean gum, guar gum, modified guar gum, maltodextrin, carboxymethylcellulose, carboxypropylcellulose, polyacrylamide, polyacrylic acid, vinyl acetate resin, acrylic ester copolymer, carbohydrate, vinyl acetate/dioctyl maleate copolymer, and acrylic polymer. 3. The adhesive patch of claim 1 wherein the biomedically active substance comprises a member selected from the group consisting of trolamine salicylate, methyl salicylate, menthol, camphor, eucalyptus oil, spearmint oil, hydrocortisone, benzocaine, lidocaine, ibuprofen, salicylic acid, capsicum. 4. The adhesive patch of claim 1 wherein the matrix includes a liquid humectant and the natural or synthetic polymer comprises a water soluble or water dispersible hydrocolloid. 5. A non-occlusive medication-containing analgesic adhesive patch for the transdermal delivery of medication into the body of a patient through the skin for the relief of pain including arthritis, backache, and muscular aches and pains comprising, a flexible pressure-sensitive adhesive matrix having a tacky pressure-sensitive surface for bonding the adhesive patch to the skin of the patient and said matrix includes: 1) a natural or synthetic water soluble or water dispersible polymer, 2) a biomedically active pain relieving substance dispersed in the adhesive matrix for being absorbed through the skin into the body of the patient comprising, a member selected from the group consisting of trolamine salicylate, methyl salicylate, menthol, camphor, eucalyptus oil, spearmint oil, hydrocortisone, benzocaine, lidocaine, ibuprofen, salicylic acid, capsicum, a flexible backing sheet for supporting the matrix, said backing sheet comprising a sheet of water insoluble material having an upper surface and a lower surface, said patch including both the backing and the matrix layer is non-occlusive with a moisture vapor transmission rate of at least about 612 g/m.sup.2 /24 hr, said adhesive matrix layer is cured so as to solidify in contact with the backing, said adhesive patch having the following portions proceeding from a lower surface of the adhesive patch to said upper surface of the backing: a) a layer of said matrix located below the lower surface of the backing, said layer having an exposed adhesive surface for bonding the patch to the skin of the patient, b) an upper portion of the matrix bonded to the backing, c) the backing having a portion that is free of said matrix, d) the backing has an upper surface that is spaced apart from the matrix, and said biomedically active substance is dispersed in the matrix such that the matrix releases the biomedically active substance into the body of the patient through said adhesive surface of the matrix that is bonded to the patient's skin. 6. The adhesive patch of claim 5 wherein the flexible pressure-sensitive adhesive matrix comprises a member selected from the group consisting of gum karaya, gum acacia, locust bean gum, guar gum, modified guar gum, maltodextrin, carboxymethylcellulose, carboxypropylcellulose, polyacrylamide, polyacrylic acid, vinyl acetate resin, acrylic ester copolymer, carbohydrate, vinyl acetate/dioctyl maleate copolymer, and acrylic polymer. 7. The adhesive patch of claim 5 wherein the pressure-sensitive adhesive matrix comprises a resin emulsion adhesive. 8. The adhesive patch of claim 7 wherein the resin emulsion adhesive comprises a member selected from the group consisting of a vinyl acetate resin, acrylic ester copolymer, vinyl acetate/dioctyl maleate copolymer, and acrylic polymer. 9. The adhesive patch of claim 5 wherein the natural or synthetic polymer comprises a water soluble or water dispersible hydrocolloid and the matrix includes a liquid humectant. 10. The adhesive patch of claim 9 wherein the humectant comprises a polyhydric alcohol. 11. The adhesive patch of claim 5 wherein the flexible backing sheet has a release coating applied to a back surface thereof. 12. A non-occlusive medication-containing analgesic adhesive patch for the transdermal delivery of medication into the body of a patient through the skin for the relief of pain including arthritis, backache, and muscular aches and pains comprising, a flexible pressure-sensitive adhesive hydrocolloidal gel matrix including: 1) a natural or synthetic polymer, 2) said polymer comprises a natural or synthetic hydrocolloidal polysaccharide, 3) a biomedically active pain relieving substance dispersed in the matrix for being absorbed through the skin into the body of the patient, 4) the biomedically active substance comprises a member selected from the group consisting of trolamine salicylate, methyl salicylate, menthol, camphor, eucalyptus oil, spearmint oil, hydrocortisone, benzocaine, lidocaine, ibuprofen, salicylic acid, capsicum, 5) a humectant comprising a polyhydric alcohol dispersed in said matrix, 6) a hydrophilic resin emulsion adhesive dispersed in the matrix for enhancing the adhesive qualifies of the matrix, a flexible backing sheet for supporting the matrix, said backing sheet comprising a sheet of water insoluble material having an upper surface and a lower surface, said patch including both the backing and the matrix layer is non-occlusive with a moisture vapor transmission rate of at least about 612 g/m.sup.2 /24 hr, said adhesive matrix layer is cured so as to solidify in contact with the backing, said adhesive patch having the following portions proceeding from a lower surface of the adhesive patch to said upper surface of the backing: a) a layer of said matrix located below the lower surface of the backing, said layer having an exposed adhesive surface for bonding the patch to the skin of the patient, b) an upper portion of the matrix bonded to the backing, c) the backing having a portion that is free of said matrix, d) the backing has an upper surface that is spaced apart from the matrix and said biomedically active pain relieving substance is dispersed in the matrix such that the matrix releases the biomedically active substance into the body of the patient through said adhesive surface of the matrix that is bonded to the patient's skin. 13. The adhesive patch of claim 12 wherein the flexible pressure-sensitive adhesive matrix comprises a member selected from the group consisting of gum karaya, gum acacia, locust bean gum, guar gum, modified guar gum, maltodextrin, carboxymethylcellulose, carboxypropylcellulose, polyacrylamide, polyacrylic acid, vinyl acetate resin, acrylic ester copolymer, carbohydrate, vinyl acetate/dioctyl maleate copolymer, and acrylic polymer. 14. The adhesive patch of claim 12 wherein the humectant comprises a polyhydric alcohol selected from the group consisting of glycerol, propylene glycol, ethylene glycol and sorbitol.