Urticaria vulgaris is a localized edematous reaction due to the expansion of small blood vessels and increased permeability of skin mucosa. It usually subsides within 2 to 24 hours, but it is easy to recur and form new lesions. The causes of urticaria are very complex, mainly including the following factors: first, food and food additives, mainly animal protein foods, such as shrimp and crab, meat, fish, eggs, etc. Second, inhalations, such as pollen, animal dander, dust, formaldehyde, etc; Third, infection, including bacteria, fungi, viruses, parasites, and so on; Fourth, drugs, many drugs cause urticaria, such as penicillin, vaccines, serum, and so on; In addition, there are physical stimuli, such as hot and cold, sunlight; Sixth, insect bites; Seventh, mental factors and endocrine changes; Eighth, genetic factors and so on. If you suffer from urticaria, it is recommended to see a dermatologist in a regular hospital.
