It is an itchy blister that recurs easily and was once known as dysphagia, appearing symmetrically on both palms and the sides of the fingers, also known as hand blisters, or on the soles of the feet, known as foot blisters. The initial damage is scattered or clusters of deep blisters, which are preceded or accompanied by a tingling or burning sensation or a severe itching in the affected area. The blisters are often found on the palms of the hands, but also on the sides of the fingers, and sometimes on the soles of the feet and on both sides of the toes, more or less symmetrically on both sides, but in some patients the blisters are more numerous on one side of the palm or the sole of the foot. The blisters contain clear fluid and the surface skin is often slightly elevated. Sometimes, adjacent blisters coalesce into large blisters of bean size or larger, and the surface skin is elevated into a hemisphere that cannot rupture naturally, often causing intense itching and even pain. The blisters are finally absorbed naturally. After the herpes of the larger blisters disappear, the blister membrane is easily removed by hand to reveal new skin of bright red color. Later, the blisters tend to recur, so the disease often lasts for weeks or months. Herpes sweat is prone to recurrence and occurs most often in the spring and fall or during the hot season. There are different causes of herpes sweat: 1, herpes sweat can be a special manifestation of eczema; 2, mental factors are one of the pathogenic factors. Anxiety or emotional stress can cause the appearance of sweat blisters, and patients often have hyperhidrosis of the hands and feet due to mental stress; 3. Sweat blisters are one of the manifestations of lichen planus rash, especially hand sweat blisters often due to the presence of tinea pedis. It is thought that about 10% of hand sweats are ringworm due to tinea pedis; 4. In a few cases, sweat blisters are a true sweating malady. Due to poor sweat ducts, excessive sweating is retained in the sweat ducts during the hot season or when there is a febrile illness, and blisters are formed. Patients with nervousness, especially with hyperhidrosis, should maintain emotional stability and apply tranquilizers or sedatives if necessary. Complicated hyperhidrosis should be treated with astringent medications such as 25% aluminum trichloride, and if necessary, oral bromobensine or prulbenecid. Sweat blisters are often a form of ringworm rash, and they can disappear spontaneously after curing tinea pedis, for example. Occasionally, blisters are the result of allergies to certain foods, bacterial infections, or medications, and they often heal spontaneously when these causes are removed. Commonly used topical medications include skin relief or other steroid hormone creams, creams formulated with steroid hormones and coal tar or furfuryl distillate, 5% salicylic acid alcohol solution, and 3% chloroiodohydroquinone cream. When the hands and feet have sweat blisters especially sweaty, daily immersion in 1:5000 potassium permanganate solution for half an hour can be beneficial. Prednisone can be taken when sweat blisters are severe.