Blisters in medicine refers to blisters, itchy blisters on the edges of the feet may be caused by ringworm of the feet, sweat herpes, eczema and other diseases. 1. Tinea pedis: the etiology is mainly related to pathogenic bacterial infections such as red trichophyton and trichophyton fungus. Patients may have clusters or scattered small blisters on the feet, often accompanied by itching. 2. Sweat herpes: the etiology is not clear, may be related to allergies, infections and other factors. The main manifestation is the appearance of blisters on the hands and feet, accompanied by intense itching itching. 3. Eczema: the cause may be related to genetic and immune abnormalities and other factors. Patients will appear local erythema, blisters, pimples and other symptoms, common in the hands, feet, head and face and other parts. Itchy blisters on the edge of the foot has more reasons, it is recommended to go to the regular hospital to check, clear cause.