What are the symptoms of acute urticaria?

From a clinical perspective, the causes of acute urticaria include allergies to fish, shrimp, and crabs, drug infection, pollen allergy, endocrine disorders, etc., and the onset of the disease is very fast. Red bumps of varying sizes will appear on the patient's skin. If not treated in time, the oral mucosa will also become abnormal, first with swelling of the lips, then laryngeal edema, followed by difficulty breathing and even suffocation.

1. Common causes of acute urticaria

① The most common foods are fish, shrimp, crab and eggs. Secondly, certain spices and condiments can also cause it.

② Drugs. There are many drugs that can cause this disease. Penicillin, sulfonamides, furazolidone, serum vaccines, etc. often cause urticaria through immune mechanisms. Drugs such as aspirin, morphine, atropine, and vitamin B1 are histamine releasers that can directly cause mast cells to release histamine and trigger urticaria.

③ Infection, including viruses (such as influenza virus, hepatitis virus), bacteria (such as Staphylococcus aureus), fungi and parasites (such as roundworms, etc.).

④ Animal and plant factors, such as insect bites or inhalation of pollen, feathers, dandruff, etc.

⑤ Physical factors such as heat, cold, sunlight, friction and pressure can cause it. In addition, gastrointestinal diseases, metabolic disorders, endocrine disorders and mental factors can also cause it.

2. Symptoms of acute urticaria

Acute urticaria often occurs acutely, with itching all over the body and wheals of varying sizes occurring when scratched. Wheals may merge into large lesions or form map-like lesions. Acute patients often present with red swollen patches, and some acute skin lesions may have blisters and bullae, which is called bullous urticaria. Purple spots may occur in the center of some areas, which is called purpuric urticaria. The mucous membrane may also be affected, causing swelling of the lips or the pharyngeal isthmus, resulting in laryngeal edema, which can cause difficulty breathing or even suffocation. The skin lesions often disappear within a few hours, but new lesions continue to occur one after another. Severe large hemorrhagic skin lesions may also disappear within a few days.

The whole body may have a fever, generally below 39°C. If it is above 39°C, attention should be paid to whether the patient has acute suppurative infection or sepsis. Respiratory symptoms may include asthma and difficulty breathing. There may be abdominal pain or stomach distension and pain in the intestines. Some may also have diarrhea. Patients with severe systemic wheal may also experience symptoms such as low blood pressure, dizziness, chest tightness, and in rare cases, shock may occur. Treatment should be given promptly. Most patients only have wheal itching symptoms and no other symptoms. The disease usually heals spontaneously within 1 to 2 weeks.