WO1998031335A2

WO1998031335A2 - Use of a serotonin antagonist and/or agonist respectively specific of the 5ht2 and 5ht1d receptor in a cosmetic or dermatological composition for sensitive skin and resulting composition

Info

Publication number: WO1998031335A2
Application number: PCT/FR1998/000062
Authority: WO
Inventors: Lionel Breton; Isabelle Nonotte; Olivier De Lacharriere
Original assignee: L'oreal
Priority date: 1997-01-16
Filing date: 1998-01-14
Publication date: 1998-07-23
Also published as: FR2758263B1; JP2001511782A; EP1014928A2; FR2758263A1; WO1998031335A3

Abstract

The invention concerns the use of an antagonist of serotonin specific of the 5HT2 receptor or of an agonist of serotonin specific of the 5HT1D receptor in a cosmetic composition or for preparing a dermatological composition for treating sensitive skin. It concerns in particular the use of an antagonist of serotonin specific of the 5HT2 receptor or of an agonist of serotonin specific of the human 5HT1D receptor for preventing and /or treating skin irritation and/or herpes and/or erythema and/or sensations of dysesthesia and /or inflammation and/or itching of the skin or for preparing a cosmetic or dermatological composition.

Description

Use of a specific serotonin antagonist or agonist of the 5HT ₂ and 5HT _1D receptor respectively in a cosmetic or dermatological composition for sensitive skin and composition obtained

The present invention relates to the use of a 5-hydroxytryptamine antagonist, also called serotonin, specific for the 5HT ₂ receptor or a 5-hydroxytryptamine agonist specific for the human 5HT _1D receptor in or for the preparation of '' a cosmetic or dermatological composition, for treating sensitive skin, including the scalp, the contours of the eyes and the mucous membranes, of human beings. It also relates to the cosmetic or dermatological composition obtained.

It is known that certain skins are more sensitive than others. However, the symptoms of sensitive skin have hitherto been poorly characterized and the problem of this skin has therefore been ill defined; no one knew exactly the process involved in the sensitivity of the skin. Some thought that sensitive skin was skin that reacted to cosmetic products, others that it was skin that reacted to several external factors, not necessarily linked to cosmetic products.

Certain tests have been tried in an attempt to identify sensitive skin, for example tests with lactic acid and with DMSO which are known to be irritating substances: see for example the article by K. Lammintausta et al., Dermatoses, 1988, 36, pages 45-49; and the article by T. Agner and J. Serup, Clinical and Experimental Dermatology, 1989, 14, pages 214-217. But these tests did not allow characterizing sensitive skin.

In addition, sensitive skin was assimilated to allergic skin. Due to the fact that little was known about the characteristics of sensitive skin, it was until now very difficult to treat them, and they were treated indirectly, for example by limiting in the cosmetic composition the use of products with an irritant nature such as surfactants, preservatives, perfumes and certain active ingredients.

The Applicant has carried out numerous clinical tests and has been able to determine the symptoms associated with sensitive skin. These symptoms are in particular subjective signs, which are essentially dysaesthetic sensations. “Dysesthetic sensations” is understood to mean more or less painful sensations felt in a skin area such as tingling, tingling, itching or itching, heating, discomfort, tightness, etc.

Furthermore, the Applicant has been able to show that sensitive skin is not allergic skin. Indeed, allergic skin is skin that reacts to an external agent, an allergen, which triggers an allergic reaction. It is an immunological process which only occurs when an allergen is present and which only affects sensitized subjects. The essential characteristic of sensitive skin is, according to the applicant, on the contrary, a mechanism of response to external factors, which can concern any individual, even if so-called sensitive skin individuals react to it faster than the others. This mechanism is not immunological.

The Applicant has now found that sensitive skin can be divided into two main clinical forms, irritable and / or reactive skin, and intolerant skin.

Irritable and / or reactive skin is skin that reacts with pruritus, that is, itching or tingling, to various factors such as the environment, emotions, food, wind, friction, razor, soap, surfactants, hard water with a high concentration of lime, variations temperature or wool. In general, these signs are associated with dry skin or skin with erythema.

Intolerant skin is skin that reacts with feelings of heating, tightness, tingling and / or redness, to various factors such as the environment, emotions, food. In general, these signs are associated with hyperseborrheic or acne-prone skin and erythema.

"Sensitive" scalps have a more unequivocal clinical semiology: the sensations of pruritus and / or tingling and / or overheating are essentially triggered by local factors such as friction, soap, surfactants, hard water with a high concentration of limestone. , shampoos or lotions, permanent conditioning products. These sensations are also sometimes triggered by factors such as the environment, emotions and / or food. Erythema and hyperseborrhea of the scalp and dandruff are frequently associated with the above signs.

In addition, in certain anatomical regions such as the large folds (inguinal, genital, axillary, popliteal, anal, submammary, elbow folds) and the feet, sensitive skin results in itchy sensations and / or dysesthetic sensations. (heating, tingling) related in particular to sweat, friction, wool, surfactants, hard water with a high lime concentration and / or temperature variations.

To determine whether a skin is sensitive or not, the applicant has also developed a test. Indeed, after having carried out a large number of tests in order to define sensitive skin, she surprisingly found that there was a link between people with sensitive skin and those who reacted to a topical application of capsaicin.

The capsaicin test consists of applying 0.05 ml of a cream containing 0.075% capsaicin to approximately 4 cm2 of skin and noting the appearance of signs. subjective effects caused by this application, such as tingling, burning and itching. In subjects with sensitive skin, these signs appear between 3 and 20 minutes after application and are followed by the appearance of an erythema which begins at the periphery of the application area.

Capsaicin causes a release of neuropeptides, and in particular of tachykinins which come from sensitive nerve endings of the epidermis and dermis. The Applicant has found that the pathophysiological pattern common to all the states of sensitive skin is linked to a great ability to release tachykinins and more particularly of substance P in the skin. The dysesthetic manifestations which are caused by the release of neuropeptides are said to be "neurogenic".

This substance P is a polypeptide developed and released by sensitive nerve endings. It induces in particular, a degranulation of mast cells resulting in particular in the release of serotonin as well as a cascade of biochemical events leading to an inflammatory reaction.

The Applicant has now discovered that one of the characteristics of sensitive skin is linked to the release of serotonin and / or to the action of this serotonin on the release and / or on certain functional aspects of the activity of substance P and therefore, the use of a serotonin antagonist specific for the 5HT ₂ receptor and / or a serotonin agonist specific for the human 5HT _1D receptor made it possible to obtain a preventive and / or curative effect for sensitive skin. Indeed, by decreasing the release and / or the synthesis of serotonin by serotoninic fibers (5HT _1D agonist) and / or by decreasing the binding of serotonin (5HT ₂ antagonist), the release and / or the activity of substance P released are greatly diminished.

To treat sensitive skin, the applicant has therefore considered using serotonin antagonists specific for the 5HT ₂ receptor or serotonin agonists specific for the 5HT _1D receptor or a combination of these antagonists and these agonists to treat sensitive skin. It has in fact surprisingly found that the incorporation of a serotonin antagonist specific for the 5HT ₂ receptor or a serotonin agonist specific for the 5HT _1D receptor in a cosmetic or dermatological composition makes it possible to avoid irritation. and / or dysesthetic sensations and / or itching of the skin.

A subject of the present invention is therefore the use of at least one serotonin antagonist specific for the 5HT ₂ receptor and / or at least one serotonin agonist specific for the 5HT _1D human receptor in a cosmetic composition or for the preparation of a dermatological composition, containing a physiologically acceptable medium, for treating sensitive skin.

Another subject of the present invention is the use of at least one serotonin antagonist specific for the 5HT ₂ receptor and / or at least one serotonin agonist specific for the human 5HT _1D receptor in a cosmetic composition or for the preparation a dermatological composition containing a physiologically acceptable medium for preventing and / or combating skin irritations and / or scabs and / or feelings of heating and / or dysesthesia and / or pruritus of the skin.

More generally, the invention relates to the use of at least one antagonist of the serotonin specific ^"5HT ₂ receptor and / or of at least one agonist of serotonin specific human 5-HT _1D receptor in a composition cosmetic or for the preparation of a dermatological composition containing a physiologically acceptable medium for treating the skin symptoms linked to the release and / or the synthesis and / or the fixation of serotonin on the 5HT ₂ receptor and / or the 5HT _1D human receptor .

A physiologically acceptable medium is a cosmetically or dermatologically acceptable medium, which is compatible with the skin, mucous membranes, nails and hair. In particular, the composition containing the serotonin antagonist and / or agonist can be applied to the face, neck, hair and nails, or any other cutaneous area of the body.

For a substance to be recognized as a 5HT ₂ receptor-specific serotonin antagonist or a human 5HT _1D receptor-specific serotonin agonist, it must inhibit the release and / or fixation and / or synthesis of serotonin in the dermis and / or the epidermis. In particular, it meets at least one of the following characteristics:

- have a selective affinity for the human 5HT ₂ or 5HT _1D receptors respectively, and / or,

- have a pharmacological activity respectively of 5HT ₂ antagonist or 5HT _1D human serotonin agonist type,

- decrease extravasation of plasma through the vascular wall induced by capsaicin or by antidromic nerve stimulation, which in both cases causes release of neuropeptide and in particular of substance P.

The ultimate goal of these reactions is to decrease the release and / or activity of neuropeptides, and in particular of substance P, released by the sensitive skin fibers.

Initially, serotonin was isolated as the vasoconstrictor principle of the blood where it is stored in red blood cells. In addition, it is found in plasma in combined form with in particular creatinine or sulfuric acid. Serotonin is also found in the central nervous system where it plays a role as a neurotransmitter. On the other hand, no one until today had established a link between serotonin and sensitive skin.

The clinical signs of sensitive skin are essentially subjective: namely tingling, tingling, itching or itching, tightness, overheating; they are sometimes accompanied by erythema. These signs are due to specific non-specific factors. According to the invention, one or more serotonin antagonists specific for the 5HT ₂ receptor can be used, one or more serotonin agonists specific for the 5HT _1D receptor or a combination of one or more of these antagonists with one or more of these agonists.

The serotonin antagonist specific for the 5HT ₂ receptor which can be used in the invention can in particular be chosen from ketanserin, cinanserin, cyproheptadine, LY 53 857, methysergide, ritanserin, ICI 169-369, risperidone, pirenperone, pipamperone, trazodone, LY 281067 and their mixtures.

The specific agonist serotonin 5HT _1D receptor used in the invention can be selected from sumatriptan sold especially under the brand Imigram ^® by Glaxo company, MK / 462, naratriptan and mixtures thereof. Preferably, sumatriptan is used. Until now, this compound was mainly used to treat migraine (see in particular the document Elsevier Science BV Ail rts. Reserv. Mathew NT.; Sanin LC Advances in migraine drug therapy).

In the composition according to the invention, the serotonin antagonist specific for the 5HT ₂ receptor and / or the serotonin agonist specific for the 5HT _1D receptor are preferably used in an amount ranging from 0.000001 to 5% of the total weight of the composition, and in particular in an amount ranging from 0.0001 to 1%.

The composition according to the invention may be in any dosage form normally used for topical application to the skin, in particular in the form of a solution or dispersion of the lotion or serum type, of emulsion of liquid or semi-liquid consistency of the milk type, obtained by dispersing a fatty phase in an aqueous phase (O / W) or vice versa (W / O), or a suspension or emulsion of soft consistency of the aqueous or anhydrous cream or gel type, of microgranules, nanoparticles, microemulsion , nanocapsules or dispersions of vesicles of ionic and / or nonionic type. These compositions are prepared according to the usual methods. It can also be used for hair in the form of an aqueous, alcoholic or hydroalcoholic solution, cream, gel, emulsion, foam or also in the form of aerosol compositions containing a propellant under pressure.

The amounts of the various constituents of the composition according to the invention are those conventionally used in the fields considered.

The composition of the invention constitutes in particular a cream for cleaning, protecting, treating or caring for the face, for the hands, for the feet, for large anatomical folds or for the body, (for example day cream, night cream, make-up remover cream, foundation cream, sunscreen cream), a fluid foundation, a cleansing milk, a body milk for protection or care, an anti-sun milk, a lotion, a gel or a skin care foam, such as cleansing lotion, sunscreen lotion, artificial tanning lotion, bath composition, deodorant composition containing bactericidal agent, after shave gel or lotion, cream depilatory, a composition against insect bites, a pain-relieving composition.

The composition according to the invention can also consist of a solid preparation constituting a soap or a cleaning bar.

The 5HT ₂ receptor-specific serotonin antagonist or the 5HT _1D receptor-specific serotonin agonist can also be incorporated into any type of composition for hair care, and in particular in a shampoo, a styling lotion, a treatment lotion , a styling cream or gel, a dye composition (in particular oxidation dye) optionally in the form of a coloring shampoo, a restructuring hair lotion, a perm composition (especially a composition for the first time of a perm), fall protection lotion or gel, etc. The composition of the invention can also be for oral use, for example in the form of toothpaste. In this case, the composition may contain adjuvants and additives customary for a composition for buccal use and in particular surfactants, thickeners or humectants, polishing agents such as silica, or various active ingredients such as fluorides, in particular fluoride sodium, and possibly sweetening agents such as sodium saccharinate.

When the composition of the invention is an emulsion, the proportion of the fatty phase can range from 5% to 80% by weight, and preferably from 5% to 50% by weight relative to the total weight of the composition. The oils, emulsifiers and coemulsifiers then used are chosen from those conventionally used in the field under consideration. The emulsifier and the coemulsifier are present in the composition in a proportion ranging from 0.3% to 30% by weight, and preferably from 0.5 to 30% by weight relative to the total weight of the composition. The emulsion may, in addition, contain lipid vesicles.

In known manner, the composition of the invention can also contain adjuvants customary in the field under consideration, such as hydrophilic or lipophilic gelling agents, hydrophilic or lipophilic active agents, preservatives, antioxidants, solvents, perfumes, fillers, filters and coloring matters. The amounts of these various ^" adjuvants are those conventionally used in the field under consideration, and for example from 0.01% to 10% of the total weight of the composition. These adjuvants, depending on their nature, can be introduced into the fatty phase, in the aqueous phase and / or in the lipid spherules.

As oils which can be used in the invention, mention may be made of mineral oils (petrolatum oil), vegetable oils (liquid fraction of shea butter, sunflower oil), animal oils (perhydrosqualene), synthetic oils (oil of Purcellin), silicone oils (cyclomethicone) and fluorinated oils (perfluoropolyethers). Fatty alcohols and fatty acids (stearic acid) can be added to these oils.

As emulsifiers used in the invention there may be mentioned for example glycerol stearate, polysorbate 60 and the PEG-6 / PEG-32 / glycol stearate sold under the name Tefose ^® 63 by the company Gattefosse.

As solvents which can be used in the invention, mention may be made of lower alcohols, in particular ethanol and isopropanol.

As hydrophilic gelling agents, mention may be made of carboxyvinyl polymers (carbomers), acrylic copolymers such as acrylate / alkyl acrylate copolymers, polyacrylamides, polysaccharides such as hydroxypropylcellulose, natural gums and clays, and, as lipophilic gelling agents , mention may be made of modified clays such as bentones, metal salts of fatty acids such as aluminum stearates and hydrophobic silica.

As hydrophilic active agents, it is possible to use proteins or protein hydrolysates, amino acids, polyols, urea, allantoin, sugars and sugar derivatives, vitamins and hydroxy acids.

As lipophilic active agents, retinol (vitamin A) and its derivatives, tocopherol (vitamin E) and its derivatives, essential fatty acids, ceramides, essential oils, salicylic acid and its derivatives can be used.

It is possible, inter alia, to combine the serotonin antagonist (s) specific for the 5HT ₂ receptor and / or the serotonin agonist (s) specific for the 5HT _1D receptor with active agents intended in particular for the prevention and / or treatment of skin conditions.

Among these active agents, there may be mentioned as an example: - agents modulating differentiation and / or proliferation and / or skin pigmentation such as retinoic acid and its isomers, retinol and its esters, vitamin D and its derivatives, estrogens such as estradiol, kojic acid or hydroquinone; - antibacterials such as clindamycin phosphate, erythromycin or antibiotics of the tetracycline class;

- antiparasitics, in particular metronidazole, crotamiton or pyrethroids;

- antifungals, in particular compounds belonging to the class of imidazoles such as econazole, ketoconazole or miconazole or their salts, polyene compounds, such as amphotericin B, compounds of the allylamine family, such as terbinafine,

- steroidal anti-inflammatory agents, such as hydrocortisone, betamethasone valerate or clobetasol propionate, or non-steroidal anti-inflammatory agents such as ibuprofen and its salts, diclofenac and its salts, acetylsalicylic acid, acetaminophen or glycyrrhetinic acid;

- anesthetic agents such as lidocaine hydrochloride and its derivatives;

- antipruritic agents such as thenaldine, or trimeprazine;

- antiviral agents such as acyclovir; - keratolytic agents such as alpha- and beta-hydroxy-carboxylic or beta-ketocarboxylic acids, their salts, amides or esters and more particularly hydroxy acids such as glycolic acid, lactic acid, salicylic acid, l citric acid and in general fruit acids, and C ₂ -C ₂₂ alkylated derivatives of salicylic acid such as n-octanoyl-5-salicylic acid;

- anti-free radical agents, such as alpha-tocopherol or its esters, superoxide dismutases, certain metal chelators or ascorbic acid and its esters;

- antiseborrheics such as progesterone; - anti-dandruff agents such as octopirox or zinc pyrithione;

- anti-acne drugs such as retinoic acid or benzoyl peroxide. As indicated above, sensitive skin is skin that reacts to external factors such as surfactants, perfumes, soaps and to all types of irritants, that is to say all types of products causing tingling. , itching, tingling, pruritus, discomfort, overheating, burning, redness, when these products come into contact with the skin.

Also, advantageously, the serotonin antagonist (s) specific for the 5HT ₂ receptor or the serotonin agonist (s) specific for the 5HT _1D receptor are associated with active agents having an irritant side effect, commonly used in the fields considered. The presence of this serotonin antagonist or agonist in a composition of the invention containing an active ingredient with an irritant effect makes it possible to strongly attenuate, or even to eliminate this irritant effect, the sufficient amount of this antagonist or agonist of serotonin to strongly attenuate, even to remove, this irritating effect being within the reach of the skilled person.

Also, the subject of the invention is also a cosmetic or dermatological composition containing a physiologically acceptable medium and at least one active agent with an irritant side effect, characterized in that it contains, in addition, at least one serotonin antagonist specific for the 5HT receptor ₂ and / or at least one serotonin agonist specific for the 5HT _1D receptor.

In particular, the active ingredients with an irritant side effect are chosen from α-hydroxy acids (fruit acid), β-hydroxy acids such as salicylic acid and its alkylated derivatives, α-keto acids, β- keto acids, retinoids, anthralins, anthranoids, peroxides, lithium salts, antimetabolites, vitamin D and its derivatives.

The present invention also relates to a cosmetic or dermatological treatment process for sensitive skin and / or sensitive scalps, characterized in that it is applied to the skin and / or hair of human beings, a composition as described above containing at least one serotonin antagonist specific for the 5HT ₂ receptor or at least one serotonin agonist specific for the 5HT _1D receptor in a cosmetically or dermatologically acceptable medium.

This treatment process can be implemented in particular by applying the composition defined above, according to the usual technique of use of this type of composition. For example: application to the skin or mucous membranes of cream, gel, serum, lotion, cleansing milk, anti-sun composition or on dry or wet hair, shampoos or after shampoos, or even application to toothpaste gums.

The following examples are given by way of illustration. In these examples, the proportions are given in percentages by weight.

EXAMPLE 1 Makeup Removing Lotion for the Face

Sumatriptan 0.0001

Antioxidant 0.05 Isopropanol 40.00

Preservative 0.30

Water qs 100%

EXAMPLE 2 Gel for Facial Care

Ketanserin 0.05

Hydroxypropylcellulose (Klucel H sold by the company

Hercules) 1, 00

Antioxidant 0.05

Isopropanol 30.00

Preservative 0.30

Water qs 100%

EXAMPLE 3 Face Care Cream (Oil in Water Emulsion)

Sumatriptan 0.002

Glycerol stearate 2.00 Polysorbate 60 (Tween 60 sold by the company ICI) 1.00

Stearic acid 1, 40

Triethanolamine 0.70

Carbomer 0.40

Liquid fraction of shea butter 12.00 Perhydrosqualene 12.00

Antioxidant 0.05

Perfume 0.5

Preservative 0.30 Water qs 100%

Example 4 Anti-Wrinkle Face Care Cream (Oil-in-Water Emulsion)

Cinanserin 0.15 Glycerol stearate 2.00

Polysorbate 60 (Tween 60 sold by the company ICI) 1, 00

Stearic acid 1, 40

N-octanoyl-5-salicylic acid 0.50

Triethanolamine 0.70 Carbomer 0.40

Liquid fraction of shea butter 12.00

Perhydrosqualene 12.00

Antioxidant 0.05

Perfume 0.5 Preservative 0.30 Water qs 100%

EXAMPLE 5 Shampoo

Ketanserin 0.0001

Lauryl ether sodium and magnesium sulfate with 4 moles of ethylene oxide, sold under the name TEAPAPON ASV by HENKEL (aήionic surfactant) 6.5 g

Hydroxypropylcellulose (Klucel H sold by the company Hercules) 1, 00

Perfume 0.50

Preservative 0.30

Water qs 100% EXAMPLE 6 Emulsified Care Gel Against Insect Bites (Oil in Water Emulsion)

Ketanserin 0.01

Purcellin oil (sold by Dragocco) 7.00

PEG-6 / PEG-32 / Glycol Stearate (TefoseR 63 from

Gattefosse) 0.30

Sumatriptan 0.02

Preservative 0.30

Perfume 0.40

Carbomer 0.60

Crotamiton 5.00

Glycyrrhetinic acid 2.00

Ethyl alcohol 5.00 triethanolamine 0.20

Water qs 100%

EXAMPLE 7 Pain Relief Gel

Sumatriptan 0.03

Hydroxypropylcellulose (Klucel H sold by the company

Hercules) 1, 00

Antioxidant 0.05

Lidocaine hydrochloride 2.00

Isopropanol 40.00

Preservative 0.30

10 Water qs 100%

EXAMPLE 8 Rosacea Care Cream for the Face (Oil-in-Water Emulsion)

15. Sumatriptan 0.025

Glycerol stearate 2.00

Polysorbate 60 (Tween 60 sold by the company ICI) 1, 00

Stearic acid 1, 40

Metronidazole 1.00

20 Triethanolamine 0.70

Carbomer 0.40

Liquid fraction of shea butter 12.00

Vaseline oil 12.00

Antioxidant 0.05

25 Perfume 0.5

Preservative 0.30

Water qs 100%

EXAMPLE 9 Care Cream for Sensitive Skins Against Solar Erythema 30 (Oil-in-Water Emulsion)

Ketanserin 0.025 18

Glycerol stearate 2.00

Polysorbate 60 (Tween 60 sold by the company ICI) 1, 00

Stearic acid 1, 40

Glycyrrhetinic acid 2.00

Triethanolamine 0.70

Carbomer 0.40

Liquid fraction of shea butter 12.00

Sunflower oil 10.00

Antioxidant 0.05

Perfume 0.5

Preservative 0.30

Water qs 100%

Claims

1. Use of at least one serotonin antagonist specific for the 5HT ₂ receptor and / or at least one serotonin agonist specific for the human 5HT _1D receptor in a cosmetic composition or for the preparation of a dermatological composition containing a physiologically acceptable medium for treating sensitive skin.

2. Use of at least one serotonin antagonist specific for the 5HT ₂ receptor and / or at least one serotonin agonist specific for the 5HT _1D human receptor in a cosmetic composition or for the preparation of a dermatological composition containing a physiologically acceptable medium for treating the skin symptoms linked to the release and / or synthesis and / or binding of serotonin to the 5HT ₂ receptor and / or the 5HT _1D receptor.

3. Use of a serotonin antagonist specific for the 5HT ₂ receptor and / or a serotonin agonist specific for the 5HT _1D receptor in a cosmetic composition or for the preparation of a dermatological composition containing a physiologically acceptable medium for preventing and / or fight against skin irritations and / or scabs and / or erythema and / or dysesthetic sensations and / or overheating sensations and / or pruritus of the skin.

4. Use according to one of claims 1 to 3, characterized in that the serotonin antagonist of type 5HT ₂ is chosen from ketanserin, cinanserin, cyproheptadine, LY 53 857, methysergide, ritanserin, ICI 169-369, risperidone, pirenperone, pipamperone, trazodone, LY 281067 and their mixtures.

5. Use according to one of claims 1 to 3, characterized in that the serotonin agonist 5HT _1D is chosen from sumatriptan, MK 462, naratriptan and their mixtures.

6. Use according to the preceding claim, characterized in that the serotonin agonist is sumatriptan.

7. Use according to one of the preceding claims, characterized in that the serotonin antagonist and / or the serotonin agonist are used in an amount ranging from 0.000001 to 5% by weight relative to the total weight of composition.

8. Use according to one of the preceding claims, characterized in that the serotonin antagonist and / or the serotonin agonist are used in an amount ranging from 0.0001 to 1% by weight relative to the total weight of composition.

9. Use according to one of the preceding claims, characterized in that the medium is an aqueous or hydroalcoholic solution, a water-in-oil emulsion, an oil-in-water emulsion, a microemulsion, an aqueous gel, an anhydrous gel , a serum, a dispersion of vesicles.

10. Use according to any one ^"of the preceding claims, characterized in that the composition contains at least one agent chosen from antibacterial, antiparasitic, antifungal, antiinflammatory, antipruritic, anesthetic, antiviral, keratolytic, anti-free radicals , antiseborrheic, anti-dandruff, anti-acne and / or agents modulating differentiation and / or proliferation and / or skin pigmentation.

11. Cosmetic treatment process for sensitive skin and / or sensitive scalp, characterized in that a composition containing an antagonist of the skin is applied to the skin and / or hair of human beings. 5HT ₂ receptor specific serotonin and / or a human 5HT _1D receptor specific serotonin agonist in a cosmetically acceptable medium.

12. Method according to claim 11, characterized in that the serotonin antagonist is chosen from ketanserin, cinanserin, cyproheptadine, LY 53 857, methysergide, ritanserin, ICI 169-369, risperidone, pirenperone, pipamperone, trazodone, LY 281067 and their mixtures.

13. Method according to claim 11, characterized in that the serotonin agonist is chosen from sumatriptan, MK 462, naratriptan and their mixtures.

14. Method according to one of claims 11 to 13, characterized in that the serotonin antagonist and / or the serotonin agonist are used in an amount ranging from 0.000001 to 5% of the total weight of the composition.

15. Method according to one of claims 11 to 14, characterized in that the serotonin antagonist and / or the serotonin agonist are used in an amount ranging from 0.0001 to 1% of the total weight of the composition.

16. Cosmetic or dermatological composition containing a physiologically acceptable medium and at least one active agent with an ^" irritant side effect ^" , characterized in that it contains, in addition, at least one serotonin antagonist specific for the 5HT ₂ receptor and / or at least a serotonin agonist specific for the 5HT _1D receptor.

17. Composition according to claim 16, characterized in that the serotonin antagonist is chosen from ketanserin, cinanserin, cyproheptadine, LY 53 857, methysergide, ritanserin, ICI 169-369, risperidone, pirenperone, pipamperone, trazodone, LY 281067 and their mixtures.

18. Composition according to Claim 16, characterized in that the serotonin agonist is chosen from sumatriptan, MK 462, naratriptan and their mixtures.

19. Composition according to claim 18, characterized in that the serotonin agonist is sumatriptan.

20. Composition according to one of claims 16 to 19, characterized in that the serotonin antagonist and / or the serotonin agonist are used in an amount ranging from 0.000001 to 5% of the total weight of the composition.

21. Composition according to one of claims 16 to 20, characterized in that the serotonin antagonist and / or the serotonin agonist are used in an amount ranging from 0.0001 to 1% of the total weight of the composition.

22. Composition according to one of claims 16 to 21, characterized in that the active ingredient with an irritant side effect is chosen from α-hydroxy acids, β-hydroxy acids, α-keto acids, β - keto acids, retinoids, anthralins, anthranoids, peroxides, lithium salts, antimetabolites, vitamin D and its derivatives.

23. Composition according to one of claims 16 to 22, characterized in that it contains, in addition, at least one agent chosen from antibacterial, antiparasitic, antifungal, anti-inflammatory, antipruritic, anesthetic, antiviral, keratolytic agents, free anti-radicals, anti-seborrheic, anti-dandruff, anti-acne and / or agents modulating differentiation and / or proliferation and / or skin pigmentation.