Transdermal patch containing capsaicin and preparation method thereof

Abstract

The invention provides a capsaicin-containing transdermal patch and a preparation method thereof.The capsaicin-containing transdermal patch comprises a backing layer, a hot-melt pressure-sensitive adhesive layer and an anti-sticking layer, the surface of the backing layer is coated with the hot-melt pressure-sensitive adhesive layer, the hot-melt pressure-sensitive adhesive layer takes styrene-isoprene-styrene (SIS) block copolymer as a thermoplastic elastomer, and the hot-melt pressure-sensitive adhesive layer takes styrene-isoprene-styrene (SIS) block copolymer as a thermoplastic elastomer; ethanol and menthol or polyethylene glycol and menthol are used as penetration promoters, compared with other types of pressure-sensitive adhesives such as polyisobutene, organic silicon and acrylic resin, in the preparation process of the transdermal patch, no organic solvent or drying equipment is needed, and the obtained transdermal patch is moderate in adhesion performance, good in oxidation resistance, small in skin irritation and free of toxic and side effects. The whole preparation process is simple and environment-friendly, and the preparation method has the advantages that the production process is safe, energy-saving and environment-friendly, the mixing property with medicines is good, and the structure is more stable.

Description

Technical Field

[0001] The invention belongs to the technical field of medicine, and particularly relates to a transdermal patch containing capsaicin and a preparation method thereof. Background Art

[0002] Capsaicin, also known as capsaicin, is a natural vanillyl alkaloid extracted from the ripe fruit of the Solanaceae plant pepper. Capsaicin has significant anti-inflammatory and analgesic effects, liver protection and liver function enhancement effects, can induce tumor cell apoptosis and has anti-tumor effects; it can also interfere with coagulation factors VIII and IX, inhibit platelet aggregation, and has cardiovascular protection effects. Foreign studies have shown that capsaicin has more obvious effects on coronary artery disease and analgesia after transdermal administration.

[0003] Capsaicin has a short half-life and a high first-pass effect in the liver, so oral administration is not the best route of administration. Capsaicin topical preparations that have been marketed in China and abroad include topical patches, creams, and gels. Capsaicin raw materials and their creams have been included in the 24th edition of the United States Pharmacopoeia and are widely used to treat diseases such as arthritis, muscle pain, back pain, sports sprains, and post-herpetic neuralgia.

[0004] Since capsaicin is slowly absorbed through the skin, the higher the concentration of the drug, the better the analgesic effect. In 2009, Averitas Pharmaceuticals, Inc. in the United States launched a high-concentration (8%) capsaicin patch that can provide up to 3 months of lasting pain relief for diabetic foot patients suffering from DPN. The patch uses silicone pressure-sensitive adhesive as an adhesive, and organic solvents need to be added during the preparation process, and the solvents need to be removed in the subsequent process. The preparation process is complicated and not environmentally friendly. Summary of the invention

[0005] The purpose of the present invention is to provide a transdermal patch containing capsaicin on the basis of the prior art. The transdermal patch comprises a backing layer, a hot-melt pressure-sensitive adhesive layer coated on the surface of the backing layer and an anti-adhesive layer, wherein the hot-melt pressure-sensitive adhesive layer uses a styrene-isoprene-styrene (SIS) block copolymer as a thermoplastic elastomer, and ethanol and menthol or polyethylene glycol and menthol as a penetration promoter. Compared with other types of pressure-sensitive adhesives such as polyisobutylene, silicone, and acrylic resin, in the process of preparing the transdermal patch, no organic solvent and drying equipment are required. The obtained transdermal patch has moderate adhesion performance, good antioxidant capacity, low skin irritation, no skin damage during peeling, and is comfortable to use. The entire preparation process is simple and environmentally friendly, and has the advantages of safe production process, energy saving, environmental protection, good miscibility with drugs, and more stable structure.

[0006] The second object of the present invention is to provide a method for preparing the above-mentioned transdermal patch containing capsaicin. The entire preparation process is simple and environmentally friendly, and has the advantages of safe production process, energy saving, environmental protection, good miscibility with drugs, and more stable structure.

[0007] The technical solution of the present invention is as follows:

[0008] A transdermal patch containing capsaicin comprises a backing layer, a hot-melt pressure-sensitive adhesive layer coated on the surface of the backing layer and an anti-adhesive layer, wherein the surface of the hot-melt pressure-sensitive adhesive layer is covered with the anti-adhesive layer, wherein the hot-melt pressure-sensitive adhesive layer is a pressure-sensitive adhesive made of active ingredient capsaicin, a thermoplastic elastomer, a permeation promoter, a tackifying resin, a plasticizer and an antioxidant; the thermoplastic elastomer is a styrene-isoprene-styrene block copolymer; the permeation promoter is ethanol and menthol or polyethylene glycol and menthol; the tackifying resin is one or more of hydrogenated rosin resin, hydrogenated terpene resin, phenolic resin, C5 petroleum resin, C9 petroleum resin or C5 / C9 petroleum resin copolymer; the plasticizer is one or more of liquid paraffin, cyclohexane oil, white mineral oil and diethyl phthalate; and the antioxidant is one or more of antioxidant 1010, thiodipropionate and styrenated phenol.

[0009] For the present invention, in a preferred embodiment, the tackifying resin is one or more of hydrogenated rosin resin, hydrogenated terpene resin or C5 / C9 petroleum resin copolymer; the plasticizer is one or more of liquid paraffin, cyclohexane oil or diethyl phthalate.

[0010] In one embodiment, the hot melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 2-10 parts of capsaicin, 10-30 parts of permeation enhancer, 25-40 parts of thermoplastic elastomer, 20-40 parts of tackifying resin, 8-15 parts of plasticizer, and 0.5-2 parts of antioxidant.

[0011] For the present invention, the preparation method of the transdermal patch comprises the following steps:

[0012] (1) mixing a plasticizer, an antioxidant, a tackifying resin and a thermoplastic elastomer uniformly, and heating the mixture to 130-150° C. so that the mixture is in a molten state to form a uniform mixed liquid;

[0013] (2) mixing the active ingredient capsaicin and the penetration enhancer to obtain an active drug solution;

[0014] (3) Cooling the mixed liquid obtained in step (1) to 80-95° C., adding the active drug solution prepared in step (2) to the cooled mixed liquid, stirring thoroughly to form a paste, coating the obtained paste evenly on the backing layer, covering the surface of the hot-melt pressure-sensitive adhesive layer with an anti-adhesive layer, and cutting into transdermal patches.

[0015] In a preferred embodiment, the hot melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18-22 parts of permeation enhancer, 28-34 parts of thermoplastic elastomer, 24-33 parts of tackifying resin, 9-13 parts of plasticizer, and 0.8-1.2 parts of antioxidant.

[0016] For example, the hot melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of ethanol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated rosin resin, 11 parts of cyclohexane oil, and 1 part of antioxidant 1010.

[0017] For example, the hot-melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of polyethylene glycol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated rosin resin, 11 parts of cyclopentane oil, and 1 part of antioxidant 1010.

[0018] For example, the hot melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of ethanol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 30 parts of hydrogenated rosin resin, 11 parts of cyclohexane oil, and 1 part of antioxidant 1010.

[0019] For example, the hot-melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of ethanol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 28 parts of C5 / C9 petroleum resin copolymer, 12.5 parts of diethyl phthalate, and 1.5 parts of thiodipropionate.

[0020] For example, the hot melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of ethanol, 2 parts of menthol, 32 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated terpene resin, 11 parts of liquid paraffin, and 1 part of styrenated phenol.

[0021] For example, the hot-melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of ethanol, 2 parts of menthol, 32 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated terpene resin, 11 parts of cyclohexane oil, and 1 part of thiodipropionate.

[0022] For example, the hot-melt pressure-sensitive adhesive layer mentioned in the present invention is made of the following components in parts by weight: 8 parts of capsaicin, 18 parts of polyethylene glycol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 30 parts of hydrogenated rosin resin, 11 parts of cyclohexane oil, and 1 part of antioxidant 1010.

[0023] The present invention also provides a method for preparing the transdermal patch containing capsaicin, comprising the following steps:

[0024] (1) mixing a plasticizer, an antioxidant, a tackifying resin and a thermoplastic elastomer uniformly, and heating the mixture to 130-150° C. so that the mixture is in a molten state to form a uniform mixed liquid;

[0025] (2) mixing the active ingredient capsaicin and the penetration enhancer to obtain an active drug solution;

[0026] (3) Cooling the mixed liquid obtained in step (1) to 80-95° C., adding the active drug solution prepared in step (2) to the cooled mixed liquid, stirring thoroughly to form a paste, coating the obtained paste evenly on the backing layer, covering the surface of the hot-melt pressure-sensitive adhesive layer with an anti-adhesive layer, and cutting into transdermal patches.

[0027] In a preferred embodiment, in step (1), a plasticizer, an antioxidant and a tackifying resin are mixed, and under the protection of nitrogen, the temperature is raised to 130-150° C. while stirring, so that the mixture is in a molten state, and then a thermoplastic elastomer is added thereto, stirred evenly, and vacuumed to remove bubbles to form a uniform mixed liquid.

[0028] In a preferred embodiment, in step (2), the active ingredient capsaicin is added to the penetration enhancer ethanol or polyethylene glycol, stirred until the capsaicin is completely dissolved, and then the penetration enhancer menthol is added thereto and stirred evenly to obtain an active drug solution.

[0029] Adopt the technical scheme of the present invention, the advantages are as follows:

[0030] The transdermal patch containing capsaicin provided by the present invention comprises a backing layer, a hot-melt pressure-sensitive adhesive layer coated on the surface of the backing layer, and an anti-adhesive layer, wherein the hot-melt pressure-sensitive adhesive layer uses a styrene-isoprene-styrene (SIS) block copolymer as a thermoplastic elastomer, and ethanol and menthol or polyethylene glycol and menthol as a penetration promoter. Compared with other types of pressure-sensitive adhesives such as polyisobutylene, silicone, and acrylic resin, in the process of preparing the transdermal patch, no organic solvent and drying equipment are required. The obtained transdermal patch has moderate adhesion performance, good antioxidant capacity, low skin irritation, no skin damage during peeling, and is comfortable to use. The entire preparation process is simple and environmentally friendly, and has the advantages of safe production process, energy saving, environmental protection, good miscibility with drugs, and more stable structure. DETAILED DESCRIPTION

[0031] The present invention can be better understood according to the following examples. However, it is easy for those skilled in the art to understand that the contents described in the examples are only used to illustrate the present invention, and should not and will not limit the present invention described in detail in the claims.

[0032] Quality evaluation method for transdermal patches:

[0033] Drug permeation rate: The Franz diffusion cell method was used to determine the in vitro drug permeation rate, and pig skin was used to simulate human skin for the experiment.

[0034] Initial adhesion: Inspected in accordance with GB4852-84.

[0035] Adhesion holding power: stick the sticky side of the test sample to the surface of the test plate, place it vertically, hang a weight (1kg) of a specified mass along the length of the test sample, and record the time it takes for the patch to fall off the adhesive plate.

[0036] Peel strength: Roll the patch back and forth 2-3 times under the roller's own gravity to make it fully contact with the test plate, and let it stand for 20 minutes. Fold the patch in half so that the peeling angle is 180°, and then test and measure the peel strength.

[0037] Oil seepage test: The invented product is coated on the test paper and placed in a 65°C constant temperature box. After 72 hours, there is no oil seepage on the back, indicating that the product is qualified.

[0038] Aging resistance: The pressure-sensitive adhesive was subjected to an aging test according to the method described in the national standard GB / T17875-1999, wherein the 180° peel strength showed no attenuation.

[0039] Comprehensive evaluation: Based on the initial adhesion, lasting adhesion, peel strength and oil penetration test results, each preparation is comprehensively rated and divided into four levels: excellent, good, fair and poor.

[0040] Example

[0041] A transdermal patch containing capsaicin is prepared from the following components in parts by weight, as shown in Table 1, wherein SIS is a styrene-isoprene-styrene block copolymer.

[0042] Table 1 Components and dosage of transdermal patch

[0043]

[0044] Wherein, the preparation method of the transdermal patch in Example 1 comprises the following steps:

[0045] (1) mixing a plasticizer (naphthenic oil), an antioxidant (antioxidant 1010) and a tackifying resin (hydrogenated rosin resin), and heating the mixture to 130-150° C. while stirring under nitrogen to make the mixture molten, and then adding a thermoplastic elastomer (styrene-isoprene-styrene block copolymer, SIS) thereto, stirring evenly, and vacuuming to remove bubbles to form a uniform mixed liquid;

[0046] (2) adding the active ingredient capsaicin to the permeation enhancer (ethanol), stirring until the capsaicin is completely dissolved, then adding the permeation enhancer (menthol), stirring evenly, to obtain an active drug solution;

[0047] (3) cooling the mixed liquid obtained in step (1) to 80-95° C. while stirring, adding the active drug solution prepared in step (2) to the cooled mixed liquid, stirring thoroughly to form a paste, coating the obtained paste evenly on the backing layer, covering the surface of the hot-melt pressure-sensitive adhesive layer with an anti-adhesive layer, and cutting into transdermal patches.

[0048] The preparation methods of Examples 2-7 refer to Example 1.

[0049] Comparative Example

[0050] A transdermal patch containing capsaicin is prepared from the following components in parts by weight, as shown in Table 2, wherein SIS is a styrene-isoprene-styrene block copolymer.

[0051] Table 2 Components and dosage of transdermal patch

[0052]

[0053] Wherein, the preparation method of the transdermal patch in Comparative Example 1 comprises the following steps:

[0054] (1) mixing a plasticizer (naphthenic oil), an antioxidant (antioxidant 1010) and a tackifying resin (hydrogenated rosin resin), and heating the mixture to 130-150° C. while stirring under nitrogen to make the mixture molten, and then adding a thermoplastic elastomer (styrene-isoprene-styrene block copolymer, SIS) thereto, stirring evenly, and vacuuming to remove bubbles to form a uniform mixed liquid;

[0055] (2) adding the active ingredient capsaicin to the permeation enhancer (ethanol) and stirring until the capsaicin is completely dissolved to obtain an active drug solution;

[0056] (3) cooling the mixed liquid obtained in step (1) to 80-95° C. while stirring, adding the active drug solution prepared in step (2) to the cooled mixed liquid, stirring thoroughly to form a paste, coating the obtained paste evenly on the backing layer, covering the surface of the hot-melt pressure-sensitive adhesive layer with an anti-adhesive layer, and cutting into transdermal patches.

[0057] The preparation methods of Comparative Examples 2-7 refer to Comparative Example 1.

[0058] The effect of different penetrant compositions on the penetration rate of transdermal patches containing capsaicin is shown in Comparative Examples 1-3. The transdermal patch containing capsaicin releases the drug into the skin to take effect through the stratum corneum of the skin. The effect of different penetration enhancers on the penetration rate of capsaicin was investigated, and the results are shown in Table 3.

[0059] Table 3 Cumulative amount of capsaicin at different times for different penetration enhancers

[0060]

[0061] As shown in Table 3, in Comparative Examples 1, 2 and 3, the cumulative amount of capsaicin is less than 0.3 ug / cm 2 It can be seen that part of capsaicin exists in the form of crystals rather than in a dissolved state, indicating that capsaicin is not completely dissolved in the hot melt pressure-sensitive adhesive. Examples 1 and 2 show that the penetration effect of capsaicin can be promoted by using a penetration enhancer combination of ethanol and menthol or polyethylene glycol and menthol.

[0062] The effects of the types and amounts of thermoplastic elastomers, tackifying resins, plasticizers and antioxidants in hot melt pressure sensitive adhesives on the adhesion properties and comprehensive physical properties of hot melt pressure sensitive adhesives are as follows:

[0063] In addition to the active ingredients, the types and amounts of thermoplastic elastomers, tackifying resins, plasticizers and antioxidants in the hot melt pressure-sensitive adhesive have a great influence on the adhesion performance and comprehensive physical properties of the pressure-sensitive adhesive. Transdermal patches containing capsaicin prepared using different types and proportions of materials were evaluated based on the adhesion performance and comprehensive physical properties of the patches. The specific composition is shown in Table 2. The adhesion and physical properties of the transdermal patches were comprehensively evaluated, and the results are shown in Table 4.

[0064] Table 4 Evaluation of adhesion and physical properties of different transdermal patches

[0065]

[0066]

[0067] The transdermal patches prepared in Examples 1-7 of the present invention have a fast penetration rate, allowing the drug to pass through the human epidermis and continuously exert an analgesic effect. The transdermal patches have moderate adhesion properties, good antioxidant capacity, low skin irritation, no skin damage during peeling, and are comfortable to use. For example, different tackifying resins, plasticizers and antioxidants are used in Examples 4, 5 and 6, and the amount of each component is within the intended range, and the adhesion and physical properties of the transdermal patch are good; there are differences in the amount of thermoplastic elastomer (styrene-isoprene-styrene block copolymer, SIS) and tackifying resin in Comparative Examples 4 and 5, and the amount is outside the protection scope of the present invention, the adhesion and physical properties of the transdermal patch are deteriorated, the peel strength of the transdermal patch in Comparative Example 5 is relatively large, which may cause skin tingling, and oil leakage occurs in Comparative Example 5, indicating poor long-term stability; the amount of antioxidant in Comparative Example 6 is low, and the aging resistance of the pressure-sensitive adhesive is deteriorated; the amount of plasticizer in Comparative Example 7 is too much, the adhesion and physical properties of the transdermal patch are deteriorated, and the oil leakage test is unqualified.

[0068] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that it is still possible to modify the technical solutions described in the aforementioned embodiments, or to perform equivalent replacements on some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A transdermal patch comprising capsaicin, characterized in that: It comprises a backing layer, a hot-melt pressure-sensitive adhesive layer coated on the surface of the backing layer and an anti-sticking layer, wherein the surface of the hot-melt pressure-sensitive adhesive layer is covered with the anti-sticking layer, and the hot-melt pressure-sensitive adhesive layer is a pressure-sensitive adhesive made of active ingredients capsaicin, thermoplastic elastomer, permeation promoter, tackifying resin, plasticizer and antioxidant; the thermoplastic elastomer is a styrene-isoprene-styrene block copolymer; the permeation promoter is ethanol and menthol or polyethylene glycol and menthol; the tackifying resin is one or more of hydrogenated rosin resin, hydrogenated terpene resin, phenolic resin, C5 petroleum resin, C9 petroleum resin or C5 / C9 petroleum resin copolymer; the plasticizer is one or more of liquid paraffin, cyclohexane oil, white mineral oil and diethyl phthalate; the antioxidant is one or more of antioxidant 1010, thiodipropionate and styrenated phenol.

2. The transdermal patch according to claim 1, characterized in that The tackifying resin is one or more of hydrogenated rosin resin, hydrogenated terpene resin or C5 / C9 petroleum resin copolymer; the plasticizer is one or more of liquid paraffin, cyclohexane oil or diethyl phthalate.

3. The transdermal patch according to claim 3, characterized in that The hot-melt pressure-sensitive adhesive layer is made of the following components in parts by weight: 2-10 parts of capsaicin, 10-30 parts of a permeation promoter, 25-40 parts of a thermoplastic elastomer, 20-40 parts of a tackifying resin, 8-15 parts of a plasticizer, and 0.5-2 parts of an antioxidant.

4. The transdermal patch according to claim 3, characterized in that, The preparation method of the transdermal patch comprises the following steps: (1) mixing a plasticizer, an antioxidant, a tackifying resin and a thermoplastic elastomer uniformly, and heating the mixture to 130-150° C. so that the mixture is in a molten state to form a uniform mixed liquid; (2) mixing the active ingredient capsaicin and the penetration enhancer to obtain an active drug solution; (3) Cooling the mixed liquid obtained in step (1) to 80-95° C., adding the active drug solution prepared in step (2) to the cooled mixed liquid, stirring thoroughly to form a paste, coating the obtained paste evenly on the backing layer, covering the surface of the hot-melt pressure-sensitive adhesive layer with an anti-adhesive layer, and cutting into transdermal patches.

5. The transdermal patch according to claim 4, characterized in that The hot-melt pressure-sensitive adhesive layer is made of the following components in parts by weight: 8 parts of capsaicin, 18-22 parts of a permeation promoter, 28-34 parts of a thermoplastic elastomer, 24-33 parts of a tackifying resin, 9-13 parts of a plasticizer, and 0.8-1.2 parts of an antioxidant.

6. The transdermal patch according to claim 5, characterized in that The hot-melt pressure-sensitive adhesive layer is made of the following components in parts by weight: 8 parts of capsaicin, 8 parts of ethanol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated rosin resin, 11 parts of naphthenic oil, 1 part of antioxidant 1010; 8 parts of capsaicin, 8 parts of polyethylene glycol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated rosin resin, 11 parts of naphthenic oil, 1 part of antioxidant 1010; 8 parts of capsaicin, 8 parts of ethanol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 30 parts of hydrogenated rosin resin, 11 parts of naphthenic oil, 1 part of antioxidant 1010; 8 parts of capsaicin, 8 parts of ethanol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 28 parts of C5 / C9 petroleum resin copolymer, 12.5 parts of diethyl phthalate, and 1.5 parts of thiodipropionate; 8 parts of capsaicin, 8 parts of ethanol, 2 parts of menthol, 32 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated terpene resin, 11 parts of liquid paraffin, and 1 part of styrenated phenol; 8 parts of capsaicin, 8 parts of ethanol, 2 parts of menthol, 32 parts of styrene-isoprene-styrene block copolymer, 28 parts of hydrogenated terpene resin, 11 parts of naphthenic oil, and 1 part of thiodipropionate; 8 parts of capsaicin, 8 parts of polyethylene glycol, 2 parts of menthol, 30 parts of styrene-isoprene-styrene block copolymer, 30 parts of hydrogenated rosin resin, 11 parts of naphthenic oil, and 1 part of antioxidant 1010.

7. The method for preparing the transdermal patch containing capsaicin according to claim 1, characterized in that: The steps include: (1) mixing a plasticizer, an antioxidant, a tackifying resin and a thermoplastic elastomer uniformly, and heating the mixture to 130-150° C. so that the mixture is in a molten state to form a uniform mixed liquid; (2) mixing the active ingredient capsaicin and the penetration enhancer to obtain an active drug solution; (3) Cooling the mixed liquid obtained in step (1) to 80-95° C., adding the active drug solution prepared in step (2) to the cooled mixed liquid, stirring thoroughly to form a paste, coating the obtained paste evenly on the backing layer, covering the surface of the hot-melt pressure-sensitive adhesive layer with an anti-adhesive layer, and cutting into transdermal patches.

8. The method for preparing the transdermal patch containing capsaicin according to claim 7, characterized in that: The tackifying resin is one or more of hydrogenated rosin resin, hydrogenated terpene resin or C5 / C9 petroleum resin copolymer; the plasticizer is one or more of liquid paraffin, cyclohexane oil or diethyl phthalate.

9. The method for preparing the transdermal patch containing capsaicin according to claim 7, characterized in that: In step (1), a plasticizer, an antioxidant and a tackifying resin are mixed, and the mixture is heated to 130-150° C. while being stirred under the protection of nitrogen, so that the mixture is in a molten state, and then a thermoplastic elastomer is added thereto, stirred evenly, and vacuumed to remove bubbles to form a uniform mixed liquid.

10. The method for preparing the transdermal patch containing capsaicin according to claim 7, characterized in that: In step (2), the active ingredient capsaicin is added to the penetration enhancer ethanol or polyethylene glycol, and stirred until the capsaicin is completely dissolved, and then the penetration enhancer menthol is added thereto and stirred evenly to obtain an active drug solution.

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