Urticaria is an allergic rash, commonly known as rash bumps, also known as rubella. The symptoms are the sudden appearance of red bumps on the skin in patches, either localized or generalized, which are very itchy. The rash may recede at first, leaving no trace, and may recur several times a day. Acute cases can be cured in a few days, while chronic cases often last for several months. The causative factors are quite complex, but it is known that certain foods, drugs, insect bites, bacterial infections, exposure to irritants and allergies to heat and cold can cause urticaria. Typical Symptoms: 1. Rash: A rash of flushed patches, varying in size and shape. It often occurs suddenly, in batches, and then fades rapidly after a few hours, leaving no trace after fading. However, it can be recurrent; 2. Itching may be accompanied by abdominal pain, nausea, vomiting, chest tightness, palpitations, dyspnea, a few have fever, swollen joints, hypotension, etc.; 3. urticaria; heat urticaria; cholinergic urticaria; sunlight urticaria; pressure urticaria; waterborne urticaria; serous urticaria; autoimmune progesterone urticaria.