How is artificial urticaria?

Artificial urticaria, also known as skin scratch, is an allergic reaction of skin blood vessels. People with this kind of artificial urticaria often feel itchy skin for no reason, but unlike ordinary urticaria, rashes will appear all over the body. Instead, when scratching the skin with nails or other blunt objects, a series of erythema wheals appear locally first, and then the edema of the wheals is higher than that of the skin, and the edges of the erythema wheals appear red and swollen, which is very similar to the traces left by the skin after being whipped. Some patients with severe symptoms will have swollen lips even if they have been bitten by teeth. Artificial urticaria can be divided into simple and symptomatic types: 1. Simple scratches: Simple scratches are physical abnormalities in normal life, and about 5% of normal people have this phenomenon. Simple skin scratches are more common in women and belong to physiological abnormal physical reactions. Its symptom is a rash after the skin is scratched by nails or other blunt objects, and most of them have no itching or other uncomfortable feelings. 2. Symptomatic scratches: Symptomatic scratches are common in young people with allergies. Most of the causes are allergic reactions of skin after external physical stimulation, which make mast cells release histamine bioactive substances, dilate skin capillaries, enhance permeability, and make plasma and tissue fluid penetrate into dermis. Symptomatic scratches can be divided into immediate and delayed types, both of which are caused by allergic reactions. The common pathogen of the former is penicillin, and this kind of allergy does not necessarily have a drug reaction first. 80% of the patients treated with penicillin were positive in skin scratch test, and some patients with artificial urticaria were still positive long after stopping penicillin. In addition to penicillin, patients with recent bacterial infections (such as acute tonsillitis, cholecystitis, appendicitis, etc.). ) and insect bites can also cause artificial urticaria with immediate symptoms. However, the occurrence of delayed symptomatic skin scratches is related to fungal allergy, and antigens are often fungal products, so patients with tinea pedis are prone to delayed symptomatic skin scratches. In addition to penicillin, patients with recent bacterial infections (such as acute tonsillitis, cholecystitis, appendicitis, etc.). ) and insect bites can also cause artificial urticaria with immediate symptoms. However, the occurrence of delayed symptomatic skin scratches is related to fungal allergy, and antigens are often fungal products, so patients with tinea pedis are prone to delayed symptomatic skin scratches. Simple artificial urticaria generally does not need treatment. For symptomatic skin scratches, we must first find the cause and remove the cause as much as possible. For example, patients who are using penicillin should stop using penicillin immediately. People infected with bacteria should be treated with anti-infection; People infected with tinea pedis and other fungi can receive antifungal treatment. Secondly, antihistamines, such as chlorpheniramine and antongding, can be used, which has certain curative effect. In addition, some drugs such as vitamin C and calcium can be used to reduce the permeability of blood vessel wall. It is worth noting that patients with artificial urticaria should not be treated with penicillin when suffering from other infectious diseases. To cure artificial urticaria, of course, we must first eliminate allergens, carry out antibacterial and antifungal treatments, avoid drug allergies, and avoid eating fish, shrimp and shellfish. It is also necessary to change the allergic constitution of patients with artificial urticaria.