It specifically refers to a hyperresponsive state of the skin under physiological or pathological conditions, which can affect any part of the body (such as scalp, external genitalia) and mainly occurs on the face. Subjective symptoms: burning, stinging, itching and tightness, skin with basically normal appearance, basic clinical characteristics of sensitive skin. Often unable to tolerate ordinary skin care products. Objective signs: with or without flaky or diffuse flushing, erythema, scales, telangiectasia, etc.

Affects patients' quality of life, and severe cases are often accompanied by psychological problems (such as anxiety or depression) Identifying whether sensitive skin is primary or secondary is crucial to treatment. High sensitivity, poor tolerance, easy to react

Europe is 25.4%~89.9%, Australia is about 50%, American women are 22.3%~50.9%, Asian women are 40%~55.98%, Approximately 36.1% of the female population in our country is female. (20%-50%) Women are higher than men The incidence rate among young people is higher than that among older people "Chinese Expert Consensus on Diagnosis and Treatment of Sensitive Skin"

Sensitive skin and "skin allergies"

Skin barrier: sebum film, stratum corneum keratin, lipids, "sandwich structure", brick wall structure, The structure composed of dermal mucopolysaccharides, etc. Function: Resist external stimulation Moisturizing protein microbial flora attached to the skin hydrophilic zone Regulate anti-inflammatory hydrophobic zone Pease PH1.5-35 Skin safe and easy to wear hydrophilic zone

brick wall theory

Factors related to skin barrier function

Mechanisms and symptoms of skin barrier damage

Factors affecting skin barrier function impairment

.Photochemical effect, biological stimulus, photothermal operation .Photothermal effect excitation effect .Photomechanical effect Mechanical effect Photochemical effect ·Light modulation effect

·Photochemical effect: Affects intercellular lipid synthesis in the stratum corneum, decreases adhesion between skin keratinocytes, and affects the "brick wall" structure. ·Photothermal effect: Thermal damage causes the denaturation of keratin in the stratum corneum, destroys the normal structure of the stratum corneum, and indirectly affects the resistance of the skin barrier. .Photomechanical effect: The mechanical stress between cells increases, destroys the integrity of keratinocytes, and causes symptoms of impaired skin barrier function.

Thermal effect of photoelectricity: ※Keratin is denatured and the normal structure of the stratum corneum is destroyed. ※The stratum corneum's anti-aging and protective functions for the skin are reduced, and pigmentation is easily formed. ※The absorption and moisturizing functions of the stratum corneum decrease, transepidermal water loss increases, and the skin becomes dry and sensitive.

Thermal effect and photochemical effect of photoelectricity: ※ Substances that affect the "mortar" of the brick wall structure: the activity of synthetic enzymes such as ceramides, fatty acids, and wax fats, leading to a decrease in moisturizing function, increased transepidermal water loss, and dry, desquamated, and sensitive skin. May affect linoleic acid and linolenic acid components. ※Reduce anti-inflammatory ability.

※Aquaporin molecules are unstable and susceptible to physical and chemical influences ※Thermal effect denatures aquaporin and loses its normal physiological function. ※Photochemical effects affect the expression of aquaporin 3 (AQP3), weakening cell migration and wound healing capabilities, causing dryness, desquamation, and aging of the skin.

※The basal layer determines the skin's self-repair and renewal. ※The basal layer cells are not damaged or damaged in a small area, and the basal cells are regenerated without scar formation. ※When the degree of damage to the basal layer cells exceeds its own repair ability, the fibrous connective tissue repairs, causing scars and discoloration.

※ Erythema, swelling, blisters, scaling, sensitivity, infection ※ Pigmentation and scars

※ Transepidermal water loss ※ Moisture content of stratum corneum ※ Skin surface PH value ※ Sebum ※Skin elasticity ※ Skin texture and wrinkles ※ Skin color ※ Scale formation rate ※ Skin thickness ※Related parameters for skin spots

·Transdermal Delivery System (TDS) Transdermal therapeutic system (TTS) refers to a drug delivery route that delivers drugs through the skin surface to achieve local or systemic therapeutic effects. ·In the field of skin treatment and medical cosmetology, the application of transdermal drug delivery systems is also limited due to the barrier function of the skin. The stratum corneum barrier makes it difficult for most drugs and methods to pass through or achieve effective concentration and effective rate.

·Injecting specific functional ingredients into the skin to achieve skin disease treatment, rejuvenation, and beautification effects It is challenging to deliver large molecule drugs and water-soluble drugs. Convenient administration and avoiding the first-pass effect of the liver

1) Compound glycyrrhizin injection (CG) can be introduced into the skin percutaneously through a pneumatic spray device; 2) Percutaneous introduction of CG can significantly inhibit inflammatory cell infiltration, and its anti-inflammatory and anti-allergic effects are similar to those of dexamethasone. The 100% CG group has the best effect. 3) CG can repair the damage of skin barrier function by down-regulating the expression level of AQP3 protein and enhancing the expression of FLG. 4) This experimental research data can provide experimental basis for the clinical application of CG introduced by air pressure spray instrument to treat inflammatory skin diseases, and provide diagnostic and therapeutic ideas and theoretical basis for further clinical treatment of skin diseases with damaged skin barrier function. Shang Yue, Yang Fengyuan, and Huang Zhao (Effects of U-injection injection prescription of oxalate-100 injection on atopic dermatitis-like mouse model) I. Chinese Journal of Dermatology and Venereology E3013619

·Skin care: cleansing, moisturizing ·Skin beauty: whitening, wrinkle removal ·Treatment of skin diseases: skin barrier repair such as acne, rosacea, facial dermatitis, eczema, hormone-dependent dermatitis, sensitive facial muscles, etc. ·Other applications: epidermal anesthesia, hair growth, underarm odor treatment, etc. ·Facial skin rejuvenation:

According to the "Cosmetics Labeling Management Regulations" promulgated by the General Administration of Quality Supervision, Inspection and Quarantine on August 27, 2007: Cosmetics refer to being spread on any part of the human body surface, such as skin, hair, fingernails, lips and teeth, etc., by smearing, spraying or other similar methods to achieve cleaning, maintenance, beautification, modification and change of appearance, or to correct human body odor and maintain Chemical industrial products or fine chemical products intended to be in good condition.

Adverse reactions to cosmetics refer to the lesions of the skin and appendages caused by people's normal use of cosmetics in daily life, as well as the human body's local or systemic damage Adverse events that do not include lesions or damage to cosmetics caused by production, occupational exposure to cosmetics and their raw materials, or the use of counterfeit and shoddy products refer to lesions or damages caused by issues such as the quality and safety of cosmetics. Hair dyes used by hairdressers cause adverse reactions? Adverse reactions caused by "Three No's" products? Adverse reactions caused by cosmetics purchased overseas? Some fake and substandard cosmetics add hormones in violation of regulations. If consumers use them for a long time, they can lead to hormone-dependent dermatitis. Currently, they are

Adverse reactions to cosmetics refer to the lesions of the skin and appendages caused by people's normal use of cosmetics in daily life, as well as the human body's local or systemic damage Adverse events that do not include lesions or damage to cosmetics caused by production, occupational exposure to cosmetics and their raw materials, or the use of counterfeit and shoddy products refer to lesions or damages caused by issues such as the quality and safety of cosmetics. Hair dyes used by hairdressers cause adverse reactions? Adverse reactions caused by "Three No's" products? Adverse reactions caused by cosmetics purchased overseas? Some fake and substandard cosmetics add hormones in violation of regulations. If consumers use them for a long time, they can lead to hormone-dependent dermatitis. Currently, they are

Serious adverse reactions to cosmetics refer to large-scale or deep severe damage to the skin and its appendages caused by cosmetics. and other systemic damage to tissues and organs. There are mainly the following 5 categories: 1. Causing temporary or permanent loss of function that affects normal human body and social functions, such as disability, disfigurement, blindness, etc.; 2. Systemic damage, such as sepsis, renal failure, etc.; 3. Congenital abnormality; 4. Life risks, such as endangerment of life, death, etc.; 5. Other serious cases requiring hospitalization. Cosmetics group adverse events refer to the same cosmetics (the same type of cosmetics produced by the same manufacturer) during the use of Medium, in a relatively concentrated period of time, to a certain number of people (10 or more people with general reactions, 3 or more people with severe reactions) Incidents that cause damage or threaten physical health or life safety and require emergency treatment "Guidelines for Monitoring Adverse Reactions to Cosmetics (Draft)"

Women use an average of 12 personal care products every day, containing 168 substances. Men use an average of 6 personal care products every day, containing 85 substances. Women use makeup every day, and on average absorb 51b of substances through the skin every year. cosmelic8 ·In the UK, the incidence of adverse reactions to cosmetics is about 23% for women and 13.8% for men. ·In the United States, 10,061 people were surveyed, 23% of women and 17.8% of men had at least one adverse reaction to cosmetics in my country, 10.83-23.5%·Schnuch A, et al. Allergy 2012 *Tammela M, et al. Contact Dermatitis, 2012 Jennifer L. Alani, et al. Dermatitis, 2013 · Zhu Keyuan et al., Journal of Practical Dermatology, 2018 ·Wu Shaolin, Research on the prevalence status and prevention and control strategies of adverse reactions to cosmetics among college students, 2019. https://www.skinsafeproducts.com/about

Adverse reactions to cosmetics =/≠Cosmetic dermatoses? Diagnostic principles: 1. Have a clear history of exposure to cosmetics before the onset of the disease 2. The primary site of skin damage is the site where the cosmetic is used 3. Exclude similar skin diseases caused by non-cosmetic factors 1 4. If necessary, conduct skin patch testing or photopatch testing of suspicious cosmetics, and further conduct testing of cosmetic allergens. skin patch test Handling Principle: GBE3-1 GBIT4-1997 1. Stop using cosmetics suspected of causing disease GBMB-1907 2. According to the clinical type and condition, treat the symptoms according to the general skin disease treatment principles. 3. Avoid further contact with identified pathogenic substances

Stimulus response - barrier destruction Allergy - cell-mediated type IV allergy IgE-mediated type 1 allergy

Cosmetic irritant contact dermatitis History of exposure to cosmetics Quick, first time use, or cumulative effect limitations, clear boundaries Pain or burning sensation, itching Predominantly itching Edema, erythema, fine debris, blisters, exudate It happens to more people after using it Remove the cause and recover quickly

Cosmetic irritant contact dermatitis Cosmetic irritant contact dermatitis History of exposure to cosmetics Used multiple times, there is an incubation period The contact area can also be extended to surrounding and distant areas or even the whole body. Swelling, erythema, papules, blisters, exudate, and scabs Fewer people experience it after using it Procrastination Patch test often positive

Differential diagnosis: eczema, seborrheic dermatitis, glucocorticoid-dependent dermatitis, photodermatitis, polymorphous light eruption Treatment: clear, deactivate, report, symptomatic, preventive In the acute phase, when the skin is slightly red and swollen, with papules and blisters, cold wet compresses with physiological sodium nitride solution or cold compresses can be used. In the chronic phase, mild skin barrier repair preparations can be used. Systemic treatment is mainly anti-allergic. Depending on the severity of the condition, oral antihistamines, vitamin C, calcium, etc. can be given. For a small number of severe patients with widespread skin lesions, short-term glucocorticoids can be used. For those with concurrent infections, antibiotics can be added. drug

A clear history of use of hair cosmetics, such as shampoo and conditioner, hair lotion, hair gel, hair dye, perm, hair tonic, decorative materials, etc. After use, hair may become brittle, split, break, fall off, lose luster, deform, etc. Can gradually return to normal after stopping use Differential diagnosis: tinea capitis, diaphyseal hair nodules, tubular hair, alopecia areata, male pattern baldness, etc. Treatment: clear, deactivate, report, symptomatic, preventive

Differential diagnosis: acne vulgaris, rosacea, occupational acne, acne caused by polycystic ovary syndrome Rabbit ear acne test and human acne test Treatment: Clear, deactivate, report, treat symptoms, prevent

Mechanism: Long-term percutaneous absorption (certain dyes, heavy metals, etc.) leads to an increase in local skin pigments Inflammatory reactions such as direct stimulation and photosensitivity stimulate melanocyte proliferation and increase tyrosinase activity. Hypopigmentation is mainly related to the destruction of melanocytes and melanin transport disorders caused by local skin inflammatory reactions. >Differential diagnosis: chloasma, Riel's melanosis, pigmented lichen planus, vitiligo, pityriasis simplex and others Treatment: The therapeutic effect of depigmentation is still uncertain; most pigmentation is temporary and can gradually reduce after discontinuation of use. Appropriate topical anti-freckle preparations can be used, and antioxidants glutathione, tranexamic acid, and vitamin C can be given if necessary. and laser

The research and development focus of functional skin care products has gradually shifted from the current "symptomatic skin care and hair care" such as moisturizing, whitening, anti-hair loss, etc. to being oriented by skin science issues, using dermatomics as a tool, multivariate statistical methods and big data as means. Select and design cosmetic raw materials and formulas based on molecular mechanisms, and advance in the direction of "targeted skin care" and "precision skin care"; Constructing a multidisciplinary collaborative subject group with cosmetic science as the core and dermatology as the basis, and organically combining the advantages and functions of each discipline into cosmetics research and development, has become a research and development trend for functional cosmetics.