Sweating disorder, often associated with hyperhidrosis, is an eczema-like reaction of the skin that occurs at the turn of the season, most often in early summer. They can be corn- to rice-sized, slightly elevated above the skin surface, with no surrounding redness. After 7-10 days the blisters dry up and become peeling and can recur, and blistering and desquamation can coexist. Patients experience varying degrees of burning and itching, often for several years. It affects the aesthetics of the hands and feet, and in severe cases, it can become secondary to infection, resulting in swelling and pain in the hands, which affects the quality of life and causes great distress to the patient. What are the causes of herpes sweat? Is it contagious? The main causes of herpes sweat are mental factors, patients with specific allergic qualities, and skin contact or ingestion of allergic substances. Mental factors such as mental tension, overwork, emotional depression, etc. are often important factors in the development of the disease; contact with irritants, bacteria, food, drug allergies, personal constitution, etc. can also be related to the occurrence of the disease; some patients have nickel sulfate allergy, so try not to contact metals and alloys containing nickel sulfate, to remove metallic dentures, do not wear necklaces and earrings containing nickel. Other conditions such as constipation and gastrointestinal disorders may also be associated with the development of this disease. Since herpes sweat is not caused by a pathogen, it is not contagious. Why is a fungal test necessary to diagnose herpes sweat? A negative fungal test is one of the most important means of differentiating tinea versicolor (commonly known as tinea pedis) from ringworm. Skin diseases that occur on the hands and feet are not limited to herpes sweat, which is also a skin disease that occurs mostly in the summer months. The principles of treatment for the two skin diseases are very different, and the doctor examines the scales of the lesions with the goal of ruling out ringworm. What are the treatments for herpes sweat? First of all, keep your hands and feet dry and clean, use some antiperspirant if necessary to reduce sweating and prevent bacterial and fungal infections; reduce contact with water and things like soap, alkali, washing powder, detergent, gasoline and alcohol; control your emotions and try to stay in a relaxed mood; avoid scratching and don’t tear the flakes with your hands to prevent infection. Frequent sufferers can do a dietary diary to find out allergic foods, pay attention to whether their sweat rash and metal are related, if necessary, you can do a patch test to confirm whether there is a nickel sulfate allergy, if there is related to try to avoid. Topical glucocorticoid ointment is the main treatment to reduce itching and control the condition, including creams containing dexamethasone, tretinoin, halometasone, mometasone furoate, hydrocortisone, etc. can be used according to the condition, and those with secondary infections can use some compound preparations containing antifungal and antibacterial agents. In severe cases, oral medication is required. Self-care can reduce the number of episodes of herpes sweat, reduce the degree of herpes sweat, but if the itching is intolerable, the effect of external medication is not good or secondary to bacterial or fungal infection, do not forget to go to the dermatological hospital as soon as possible.