JP2004307489A - Antipruritic composition for external application - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition which has an antipruritic effect and a good appearance and impression at use. <P>SOLUTION: The antipruritic composition for external application contains 0.5-20. wt.% mucopolysaccharides or derivatives thereof. The mucopolysaccharides preferably comprise at least one selected from the group consisting of hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, heparin, chitin and chitosan. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a composition having an excellent skin antipruritic effect.

Conventionally, antihistamines, steroids and the like have been prescribed as external pruritus preparations for itching of the skin, but these drugs do not always provide a sufficient antipruritic effect.
In particular, the mechanism of the onset of dry itch is not clear, and there is no specific treatment method at present.
Furthermore, the causes of these itch are not uniform, and the above-mentioned drug may be effective in itch due to atopic dermatitis, but it is effective against dry itch, senile pruritus and pruritus after renal dialysis. Has little effect on the above drugs. This is because the quality of the itch varies.
On the other hand, moisturizers such as urea and petrolatum are used to prevent drying of the skin, but it cannot improve itch due to drying. Mucopolysaccharides are also sometimes used as moisturizers, but their antipruritic effect is not known at all (Non-Patent Document 1).

Guide to Cosmetic Ingredients, 2nd Edition, Fragrance Journal, April 2002

The present invention has been made in view of the above circumstances, and has as its object to provide a composition having a wide range of antipruritic effects on various pruritus.

The present inventors have conducted intensive studies and found that mucopolysaccharide or a derivative thereof exhibits a strong antipruritic effect at a concentration of 0.5 to 20% by weight.
That is, the present invention is an external composition for skin pruritus, comprising 0.5 to 20% by weight of mucopolysaccharide or a derivative thereof.
Hereinafter, the present invention will be described in detail.

The topical composition for skin pruritus of the present invention contains a mucopolysaccharide or a derivative thereof.
The mucopolysaccharide means a polysaccharide containing hexosamine as a constituent. The mucopolysaccharide is not particularly limited, but is preferably, for example, at least one selected from the group consisting of hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, heparin, chitin, and chitosan. Further, the above-mentioned mucopolysaccharide derivative means a compound produced by a change in a small part in the molecule of the above-mentioned mucopolysaccharide, and examples thereof include hyaluronate and chondroitin sulfate.

The mucopolysaccharide or a derivative thereof preferably has an average degree of polymerization of 5 or more and less than 1200. If it is less than 5, the skin antipruritic effect may not be sufficiently obtained, and if it is 1200 or more, the physical properties may be changed, and the skin antipruritic effect may not be sufficiently obtained. The more preferable average polymerization degree is 10 or more and less than 1000, and further preferably 50 or more and less than 800.

The content of the mucopolysaccharide or a derivative thereof is preferably 0.5 to 20% by weight.
If the amount is less than 0.5% by weight, a sufficient antipruritic effect on the skin may not be obtained. If the amount is more than 20% by weight, no further effect can be expected. The ability to follow the skin may be poor. A more preferred content is 0.5 to 10% by weight,
It is more preferably from 0.5 to 8% by weight, particularly preferably from 1 to 6% by weight, most preferably from 1 to 4% by weight.

When chitosan or a derivative thereof is used as the mucopolysaccharide or a derivative thereof, the composition for external use for skin pruritus of the present invention preferably contains an acid to make the chitosan or a derivative thereof water-soluble.
As the acid, either an inorganic acid or an organic acid can be used. As the inorganic acid,
For example, hydrochloric acid, phosphoric acid, sulfuric acid, nitric acid and the like can be mentioned. Examples of the organic acid include acetic acid, succinic acid, malic acid, lactic acid, butyric acid, fumaric acid, malonic acid, itaconic acid, gluconic acid, glycolic acid, tartaric acid, citric acid and the like. Among them, a hydroxy acid which is a fatty acid having a chemical structure having a hydroxyl group in a carboxylic acid is preferable. These acids may be used alone or in combination of two or more.
The content of the acid is preferably 0.1 to 10% by weight. If the amount is less than 0.1% by weight, chitosan or a derivative thereof may not be sufficiently soluble in water. If the amount exceeds 10% by weight, skin irritation may be exhibited depending on the application site. A more preferred content is 0.5 to 5
% By weight.

The composition for external use for skin pruritus of the present invention preferably further contains liquid oils in order to improve the spreadability and give a good feeling of use. The liquid oils are not particularly limited, and include, for example, hydrocarbons such as squalane and glyceride oils such as triglyceride. Among them, squalane is particularly preferred.
The content of the liquid oils is preferably 2 to 20% by weight, more preferably 5 to 1% by weight.
5% by weight.

It is preferable that the composition for external use for skin pruritus of the present invention further contains urea.
The above mucopolysaccharides, especially chitosan, in an aqueous solution, the Maillard reaction is likely to occur due to heat and browning may occur.However, the present inventors have found that the addition of urea stabilizes chitosan and the like to prevent browning. I found what I can do.
The urea content is preferably 0.1 to 3% by weight. If the amount is less than 0.1% by weight, a sufficient effect may not be obtained. If the amount exceeds 3% by weight, not only the effect does not increase any more, but also mucopolysaccharide is precipitated, and it becomes difficult to formulate the preparation. Sometimes. A more preferred content is 0.1 to 1.5% by weight.
The composition for external use for skin pruritus of the present invention contains, for example, compounds having a sulfur atom, such as sulfite, which may lose the effects of the present invention. Preferably not.

The composition for external use for skin pruritus of the present invention includes powders, oils, surfactants, thickeners, organic solvents, plasticizers, dyes, pigments, fragrances, preservatives, and antioxidants as long as the object of the present invention is not impaired. And the like.

The dosage form of the composition for external use for skin pruritus of the present invention is not particularly limited, and examples thereof include ointments, creams, and liquids. Examples of the liquids include gels, sols, aqueous solutions, and alcohols. Agents, glycerin / glycol agents, oils, suspension lotions, emulsion lotions,
Varnishes, poultices, sprays and the like can be mentioned.
The method for producing the composition for external use for skin pruritus of the present invention is not particularly limited, and it can be produced by a conventionally known method.

The application amount of the composition for external use for skin pruritus of the present invention is not particularly limited by the type and concentration of the active ingredient and the condition of the site to be applied, but is usually one to several times a day, 0.01 to 10 g / time. It is preferable to apply the degree. The application method of the composition for external use for skin pruritus of the present invention is not particularly limited. In addition to the usual method for applying an external preparation for skin using an instrument such as a finger or a spatula, a pump method, a spray method,
A method of applying directly from a tube-type container, a method of compressing, and the like are included.

The composition for external use for skin pruritus of the present invention can remarkably reduce pruritus, dry pruritus, atopic dermatitis, dermatitis pruritus such as contact dermatitis, senile pruritus or after renal dialysis Itching,
Furthermore, it is also effective against itching such as eczema, rash, urticaria, rash, insect bite, morbidity and soreness.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

(Examples 1 to 20)
Mucopolysaccharide was added to water for injection (manufactured by Otsuka Pharmaceutical Co., Ltd.) so as to have the content (% by weight) shown in Table 1, stirred, and chitosan (average degree of polymerization was 30 or 300, manufactured by Wako Pure Chemical Industries) only Lactic acid (manufactured by Kosakai Pharmaceutical Co., Ltd.) was added and dissolved to obtain compositions of Examples 1 to 20.

(Comparative Examples 1 to 5)
Mucopolysaccharide was added to water for injection (manufactured by Otsuka Pharmaceutical Co., Ltd.) so as to have the content (% by weight) shown in Table 1, stirred, and chitosan (average degree of polymerization was 30 or 300, manufactured by Wako Pure Chemical Industries) only Lactic acid (manufactured by Kosakai Pharmaceutical Co., Ltd.) was added and dissolved to obtain compositions of Comparative Examples 1 to 5.

(Examples 21 to 46)
Mucopolysaccharide was added to water for injection (manufactured by Otsuka Pharmaceutical Co., Ltd.) so as to have the content (% by weight) shown in Table 1, stirred, and chitosan (average degree of polymerization was 30 or 300, manufactured by Wako Pure Chemical Industries) only Add lactic acid (Kosaka Pharmaceutical Co., Ltd.) and dissolve, then add squalane (Maruha Co.) and urea (Kosaka Pharmaceutical Co.)
Was added so as to have a content (% by weight) shown in Table 1 and suspended and emulsified to obtain compositions of Examples 21 to 46.

(Evaluation 1)
Each composition of Examples 2, 6, 10, 14, 18, 22, 26, 30, 34, 38, and 43 to 46 was evaluated by the following method. The results are shown in Table 2.

<Sensory evaluation by healthy people>
Sensory evaluation was performed on the appearance and feeling of use by a healthy person. 5:
Very good, 4: good, 3: neither good, 2: slightly bad, 1: bad. The higher the value, the better the feeling of use.

As is clear from the results shown in Table 2, by containing urea and liquid oils, more preferable appearance and feeling of use were exhibited.
(Evaluation 2)
Each composition of Examples 1, 4, 6, 11, 14, 17, 20, and 38 and Comparative Examples 1 to 3 and 5 was evaluated by the following method. The results are shown in Table 3.

<Evaluation of pruritus>
Six patients with itch (two males and four females) were evaluated for antipruritic properties by a single application of the external preparations obtained in the above Examples and Comparative Examples. Immediately after application, 3: Effective, 2: Effective, 1: Neither, 0: Invalid, and 3 or 4 out of 6 patients were evaluated as 2 or more, and the effective rate was evaluated. evaluated. The higher the effective rate, the higher the antipruritic property.

As is clear from the results shown in Table 3, the examples containing 0.5% by weight or more of the mucopolysaccharide were:
It showed a strong antipruritic effect.

ADVANTAGE OF THE INVENTION According to this invention, the composition which can achieve both the excellent skin antipruritic effect and favorable feeling of use can be provided.

Claims (5)

An external composition for skin pruritus, comprising a mucopolysaccharide or a derivative thereof in an amount of 0.5 to 20% by weight. The composition for external use for skin pruritus according to claim 1, wherein the mucopolysaccharide is at least one selected from the group consisting of hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, heparin, chitin and chitosan. . The topical composition for skin pruritus according to claim 1 or 2, wherein the mucopolysaccharide or a derivative thereof has an average degree of polymerization of 5 or more and less than 1200. 4. The composition for external use for skin pruritus according to claim 1, further comprising a liquid oil. 5. The composition for external use for skin pruritus according to claim 1, further comprising urea.