Itchy blisters on the palms of the hands, consider and sweat herpes, eczema, insect bite dermatitis and other factors. 1. Sweat herpes: the etiology is still unclear, may be related to allergies, skin bacterial infections, long-term in hot and humid climate, etc., a variety of factors caused by sweating not good eczema. Patients will mainly appear lesions with small blisters, symmetrical distribution, blisters above the skin surface, accompanied by varying degrees of itching. 2. Eczema: If the patient is intolerant to allergens, so that the hands in contact with allergens, such as dust mites, dust, animal dander, etc., which will lead to allergens to stimulate the body’s immune system, so that the patient appeared on the palms of the long blisters, itchy symptoms, accompanied by redness, swelling, oozing, and other acute inflammatory reaction. 3. Insect bite dermatitis: If the patient’s palms are bitten by fleas, mosquitoes, bees and other insects, the insects will inject saliva into the skin during the bite, which will make the human body have an allergic reaction, thus leading to insect bite dermatitis, resulting in the palms of long blisters and very itchy symptoms, accompanied by localized pain, redness and swelling of the symptoms. When the patient’s palm long blisters, need to go to the hospital in time for a comprehensive examination, clear cause, under the guidance of the doctor to choose the appropriate method of symptomatic treatment.