2, mental factors cause intractable urticaria. Mental stress, mood swings and depression can also be the inducing factors of urticaria.
3, food causes intractable urticaria. Mainly animal protein foods, such as fish, shrimp, crab, eggs, milk and other seafood, are common pathogenic factors. Some fruits and vegetables can also be sensitized. Adding condiments, preservatives and pigments to food, and natural or synthetic substances in food such as salicylic acid and citric acid can also cause urticaria.
4. Physical factors cause intractable urticaria. Such as cold and heat, sunshine, friction and pressure. In addition, gastrointestinal diseases, metabolic disorders, endocrine disorders and mental factors can also be caused.
5. The disease causes intractable urticaria. Such as gastrointestinal diseases, tumors, connective tissue diseases, endocrine disorders and metabolic disorders. It will also be the cause of urticaria.
6, animal and plant factors, such as insect bites or inhalation of pollen, feathers, dander, etc.