Allergic dermatitis

Introduction to allergic dermatitis Allergic dermatitis (allergicdermatitis) is a skin allergic reaction caused by exposure to allergic antigens, which is mainly caused by IgE-mediated type I allergy. Anyone who is genetically or physically susceptible to a specific antigen may cause immediate or delayed atopic dermatitis when exposed to this antigen, mainly because the human body is exposed to certain allergens and causes redness and swelling of the skin. Itchy skin, wheal, peeling and other skin conditions. Specific allergens can be divided into four categories: contact allergens, inhaled allergens, ingested allergens, and injected into allergens. Each type of allergen can cause a corresponding allergic reaction, the main manifestations are a variety of dermatitis, eczema, urticaria, when allergic dermatitis occurs, the cause should be found as soon as possible, good care, and early treatment. Keep away from allergenic factors, this is the most fundamental way to prevent allergic dermatitis. Minimize allergens in the environment, such as inhaled allergens (all substances that can be inhaled through the respiratory tract are potential allergens), including dust, dust mites, cotton wool, pollen (spring and summer and autumn), animal hair, Fungi, insects and smoke. basic knowledge Sickness ratio: 0.5% Susceptible people: people with allergies Mode of infection: non-infectious Complications: pruritus

Causes of allergic dermatitis

Primary irritation (40%):

It is mainly caused by strong acids, strong bases, cantharidins and certain chemicals that are more irritating or concentrated. This type of individual is non-selective and has no incubation period, and any person's exposure can immediately cause acute inflammation of the skin.

Allergic reaction (50%):

This type is mainly a delayed allergic reaction (v1 type allergic reaction). It is caused by exposure to certain stimulating factors (allergens) on the skin and mucous membranes, and only a few people with specific allergies are ill. It does not immediately develop after initial contact, but often after 4-20 days of incubation (average 7 - 8 days) The body is first sensitized. If the substance is contacted again, dermatitis can occur within about 12 hours (generally no more than 72 hours). Such allergic reactions are common in contact dermatitis.

There are many types of irritants that cause contact dermatitis:

1. Various animal skins, some animals such as bees, jellyfish, cockroaches, dust mites, butterflies, moths, etc.

2. Chemical substances, most contact dermatitis is caused by chemical irritants, such as drugs, dyes, detergents, oils, cosmetics, chemical fibers, plastic products, chemical raw materials, contraceptives, straps, nail polish Wait.

3. Phytophysical, mainly including mustard, croton, garlic, ramie, pyrethrum and the like. The shape, extent and severity of the lesion depend on the type, nature and concentration of the contact, the length of the contact, the size of the contact and the area, and the extent to which the human body responds to the irritant. Light localized skin congestion, clear pale blood spots on the edges; severe cases of papules, leeches (or cockroaches), erosion, exudation, etc. on the basis of erythema. Light people consciously itching, heavy people feel pain.

4. When I was a child, I had more antibiotics because of a cold. I also found that most people suffer from allergic dermatitis.

Allergic dermatitis prevention

1) Reduce the induced aggravating factors and stimulating factors such as mechanical factors (scratch, friction), physical and chemical factors (hot water washing, high temperature, low humidity, irritating drugs), biological factors (animals and plants, microbial infections, etc.), nervousness Or depression or digestive dysfunction.

2) Keep away from allergenic factors, this is the most fundamental way to prevent allergic dermatitis. Minimize allergens in the environment, such as inhaled allergens (all substances that can be inhaled through the respiratory tract are potential allergens), including dust, dust mites, cotton wool, pollen (spring and summer and autumn), animal hair, Fungi, insects and smoke. Food allergens (allergens that cause allergic reactions through ingestion), including fish, shrimp, crab, beef and mutton, eggs, milk, peanuts, soybeans and nuts. Contact allergens (allergens that cause allergies through contact with the skin or mucous membranes), including clothing, dyes, cosmetics, jewelry, topical medicines, paints, organic solvents, hair dyes, and disinfectants. In order to create a healthy and hygienic environment, always maintain indoor hygiene, open windows and ventilation, maintain proper temperature and humidity, do not use disinfectants casually, keep children in contact with pollen in spring, avoid direct sunlight in summer, do not raise pets at home, especially in indoors. Use less carpet, vacuum, do not use electric blankets, avoid irritating cosmetics.

3) Care for the skin, bathe scientifically and reasonably, choose pH neutral, non-irritating soap, non-invasive skin care products, underwear should choose soft cotton fabric, should not wear wool, chemical fiber fabric, these fabrics are rough, and It is irritating to the skin and is prone to dermatitis and eczema.

Allergic dermatitis complications Complications pruritus

The cause is removed, the simple erythema subsides within a few days, and the blisters are dry. Blisters and large bubbles can rupture, exudate and scar. If the inflammation subsides, there are scales, and sometimes the skin will temporarily thicken. Continued contact with pathogenic factors or complications (such as irritation or topical allergy, epidermal exfoliation, infection) can persist dermatitis.

Allergic dermatitis symptoms Common symptoms Allergic dermatitis Skin itching erysipelas appearance Pediatric eczema Iodine allergy

Allergic dermatitis

Atopic dermatitis is an inflammatory reaction of the skin caused by many factors. There are two main types of common allergic dermatitis: contact dermatitis and cosmetic dermatitis. Allergic reactions caused by different pathogenic factors are different.

Allergic dermatitis Contact dermatitis is an acute inflammatory reaction of the skin caused by contact with an external stimulating substance on the skin or mucosa. The causes can be divided into two categories: primary stimuli, mainly caused by strong acids, strong bases, cantharidins and certain chemicals with strong irritancy or concentration. This type of no individual selectivity, and no incubation period, any person can immediately cause acute inflammation of the skin; allergic reaction (allergic reaction), this type is mainly delayed allergic reaction (v1 type allergic reaction). It is due to the exposure of certain stimulating factors (allergens) to the skin and mucous membranes. Only a few people with specific allergies develop symptoms. They do not develop immediately after initial contact, but often have an incubation period of 4-20 days (average 7 - 8 days) The body is first sensitized. If the substance is contacted again, dermatitis can occur within about 12 hours (generally no more than 72 hours). This type of allergic reaction is the most common in contact dermatitis.

Skin inflammation caused by cosmetics, called cosmetic dermatitis. Some people often use certain cosmetics, and once they are stopped or used again, allergic reactions will occur; others will have an allergic reaction in the back of the first use, and some will react after exposure to sunlight.

In most patients, allergies occur within a few hours after the use of cosmetics. This is called an immediate (or immediate) allergic reaction in medicine; a delayed response occurs after several days of allergic reactions. Generally, there are more reactions in an immediate form. Cosmetic dermatitis is only partial skin itching, a little scattered red pimples, erythema and mild swelling, severe local skin edema, diffuse erythema, leeches of varying sizes, and even exudate erosion.

Contact dermatitis

It is due to the acute skin inflammatory reaction at the contact site after exposure of certain substances to the skin and mucous membranes. The causes can be divided into primary stimuli and allergic reactions. Clinical manifestations include erythema, blisters, bullae, and even necrosis. The course of the disease is self-limiting.

Cosmetic dermatitis

Cosmetic dermatitis is caused by cosmetic skin inflammation, called cosmetic dermatitis. Cosmetics have become an indispensable part of people's daily lives. Some people often use certain cosmetics, and once they are stopped or used again, allergic reactions will occur; others will have an allergic reaction when they use the back part for the first time; others will react after exposure to sunlight.

In most patients, allergies occur within a few hours after the use of cosmetics. This is called an immediate (or immediate) allergic reaction in medicine; a delayed response occurs after several days of allergic reactions. Generally, there are more reactions in an immediate form.

Examination of allergic dermatitis

1. The contact dermatitis examination project caused by allergic reaction is mainly based on the inspection frame limit "A";

2, the case caused by the primary irritant, the lesion range is widely associated with systemic symptoms, the examination project may include the inspection of the box "A", "B".

3. Allergen examination.

Diagnosis and differentiation of allergic dermatitis

Insect bite: The typical skin lesion is a wheal-like papule with a small blister at the top and no systemic symptoms.

Drug eruption: There is a clear medication, there is a certain incubation period, skin lesions suddenly occur, in addition to the fixed drug eruption, more symmetric distribution.

Hemorrhoids: There is a history of contact infection, a good site and a typical skin lesion. If you can find it, you can confirm the diagnosis.

Judgment method 1:

Acute eczema sensitive physical self-test

Is a sensitive constitution diagnosed by a physician, or has a family history of allergies

Use acid care products, if it is sour, it will have a tingling sensation

Drinking alcohol or being in a non-ventilated room for a long time, the skin will be red and hot

There will be winter itching, dry skin in the outer oil, oily skin but it looks dull

The skin is very thin, it turns red when it is exposed to the sun, and it reveals a cyan blood vessel when it is not reddish.

If the above symptoms are more than three, it is basically a sensitive constitution.

Temporary sensitive self-test

As long as you stay up all night, the skin will be red and itchy every other day.

After exposure, the skin is red and will not fade for a long time.

Sensitive symptoms occur when stress is too high or fatigue

The skin will peel off or itching during the season when it is hot and cold, or when the humidity increases.

Every time before menstruation, the skin will become rough and rash or peeling

If the above symptoms are more than three, it is basically a sensitive skin.

Judgment method 2:

(1) When replacing a long-lasting cosmetic brand, the skin may not be able to adapt for a while;

(2) has a history of skin diseases, the skin is more fragile;

(3) It is easier to have acne or blisters than the average person;

(4) Even if the jitter is smashed, the curtain fabric is likely to cause itching;

(5) When the seasons alternate, the skin quality changes are significantly different from normal;

(6) The skin is prone to use a product such as fruit acid to produce a burning tingling sensation;

(7) Allergies to sweat, eye drops, swimming pool water, etc.;

(8) For physical stimulation such as massage or temperature changes, skin redness and other phenomena occur.

If one or more of your skin conditions occur in one of the above eight symptoms, then most of you are sensitive skin. In addition to the above conscious reactions, sensitive skin is characterized by the following common skin characteristics: thin keratin, dry skin, prone to acute irritation, and poor resistance to mechanical friction.

Judgment method 3:

A: General symptoms:

1. Itching after sweating will cause pain

2, the skin is always very rough, often peeling

3, often because of stress or fatigue

4, a new cosmetic, the skin will have problems

5, in the past one or two years, the use of cosmetics caused by skin inflammation, rash, sun exposure to ultraviolet light, the skin will be red, pain.

B: Symptoms of using cosmetic care:

1. After washing your face, your skin will be tight and red. <This is weak horny defense function>

2, wipe the lotion, the skin often has a tingling sensation. <This is a weak keratin defense function, alcohol allergy>

3, wiped the high moisturizing beauty liquid, the skin will be itchy, stinging <Humectant allergy>

4, sunscreen products are not suitable for you <UV absorber allergy>

5, massage or apply mask, you will feel the stimulus <physical stimulation allergy>

C: Physical and environmental factors:

1, suffering from flower fen, can be allergic to metals and other items

2, the skin is fragile, usually easy to grow eczema

3, allergic to nylon, rubber, chemical fiber and other substances

4. When the season changes, the skin condition will be unstable.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.