Do you know what causes 'hives'?

 

Hives caused by certain stimuli, such as food, temperature, or clothing scratching, can be exacerbated by the itching and biting. Repetitive events can cause stress, lack of sleep, and interfere with your daily life. This time, we will explain the characteristics, symptoms, causes, typical diseases, and medical subjects of urticaria.

What is hives?

What is urticaria?

Hives is a disease in which a part of the skin suddenly turns red and disappears without a trace after a while. It is characterized by itching and may be accompanied by a stinging itch or a burning sensation (burning sensation) of the affected area. Hives, unlike viral rashes, do not spread from person to person. Distinguish between acute urticaria and hives lasting more than 1 month from chronic urticaria. Hives with known causes account for 1 to 3% of cases, and in most cases, the cause is unknown.

hives symptoms

What are the main symptoms of hives?

Hives are characterized by symptoms such as redness and swelling (wheps) resembling mosquito bites. Hives can be large and small, and when the wheal is connected, it may appear like a map and spread all over the body. Hives are often intensely itchy, accompanied by a stinging or burning burning sensation. In chronic hives, symptoms appear from the evening to the night, and hives may appear at a set time. If hives persist, consult a medical institution and control the symptoms with underwear, etc.

How long does hives last?

Hives usually disappear without a trace within 24 hours. Most of these go away within a few hours, which is characteristic of hives. However, hives may not go away after 24 hours or more. This case is called urticaria-like erythema, and distinguishes it from another disease.

Where do hives appear on the body?

Hives can occur anywhere on the body, including the face. In particular, it is known that it is easy to develop in areas with soft skin such as the thigh, abdomen, buttocks, back of the knee, cheeks, and neck. Other than that, it seems that rashes may also occur on the soles of the feet, the backs of the hands, and the scalp. However, biting hives may increase the scope of the hives. If it occurs in the mouth, pharynx, or airways, it may itch and cause shortness of breath or choking. Stimulation temporarily relieves the itch, but it is important not to irritate the affected area as it can lead to a vicious cycle because the scope of hives is widened.

What causes hives?

There are allergic urticaria, non-allergic urticaria, and idiopathic urticaria. Allergic urticaria and non-allergic urticaria are characterized by reactions to specific allergens contained in food or drugs. In some cases, it is an allergic reaction to food such as eggs, wheat, or shellfish, and in other cases, it is caused by antibiotics or antipyretic analgesics. In some cases, it may be caused by irritation such as sweat, sunlight, scratching or pressure on clothing, or stress or overwork in other cases. Treatments for hives differ depending on the cause, so consult a medical institution when symptoms recur.

allergic urticaria

How does allergic urticaria develop?

A well-known cause of hives is type I (immediate type) allergy. When substances that cause allergies, such as antigens or allergens, enter the body, antibodies against the allergen are activated, causing a hives reaction. Representatives of allergic urticaria are food, dust, and pollen.

non-allergic urticaria

How does non-allergic urticaria develop?

Symptoms occur when the body's antibodies against the allergen are activated in a structure different from that of allergic urticaria. Non-allergic urticaria is temperature or environment. However, its structure has hardly been elucidated.

idiopathic urticaria

How does idiopathic urticaria happen?

Hives also occur when there is a specific cause, such as a specific food, irritation from cold or heat, or mechanical irritation. However, in more than 70% of hives, the direct cause is not clearly known. Symptoms that appear or subside over several days are called idiopathic urticaria.

A typical disease that causes hives

Please tell me the typical diseases that cause hives.

Typical diseases that cause hives include viral hepatitis, thyroid disease, and gastritis. These are known to be prone to hives. In addition, urticaria may occur as part of systemic diseases including the skin, such as collagen disease, serum disease, and vasculitis. If you have hives and wonder if they are related to other diseases, but if the hives disappear within a few hours and there are no subjective symptoms other than skin symptoms, then there is no need to suspect the disease right away.

Urticaria examination subject

Which department should I see if I have hives?

Basically, let's see a dermatologist. In some cases of hives, hives appear due to collagen disease, so if the symptoms seem to be recurring, get a detailed examination at the internal medicine department.

Urticaria test

What tests are needed for hives?

Allergic urticaria can be tested relatively easily with a blood test or skin test. What kind of test is using the skin? When using the skin, detailed tests such as a test in which a substance suspected to be the cause is injected into the skin called an intradermal test or a prick test in which a substance suspected to be the cause is placed on the skin and pricked with a needle. However, even if the test result is positive with this method, not all symptoms are the cause of hives. In the final diagnosis, the symptoms and progress made so far are comprehensively judged.

What tests will be done if it is non-allergic? If hives are caused by idiopathic stimuli due to physical stimuli such as heat, cold, or light, apply the stimulus that induces hives and check whether hives actually occur. In the case of other non-allergic urticaria, it is determined whether there is urticaria by examining the disease that is suspected to be a symptom other than the disease or skin that has occurred before.

Sex and age differences in urticaria

Are there gender differences and age differences in hives?

Hives are a relatively common condition, and 15-20% of people will experience it at least once in their lifetime. Because there are individual differences in the cause of hives and allergens, it occurs in a wide range of people, from babies to the elderly, and there is no difference between men and women.

organize

Hives are caused by any stimulus, such as food, temperature, or clothing scratches. It is characterized by strong itching and is often accompanied by a burning sensation, and it is characterized by being easy to fall into a vicious cycle, such as aggravating symptoms by scratching at the itch. Because repetitive events can cause stress, lack of sleep, and interfere with daily life, symptoms can be suppressed with underwear. It is easy to develop on softer skin, so it is important not to scratch even if symptoms develop. When symptoms recur, consult a dermatologist or internal medicine department, and begin treatment as soon as possible.