Behind the ear itchy a scratch running water may be the outer ear eczema, contact dermatitis and other diseases.
1. Eczema of the outer ear: the etiology of this disease is not clear, research has shown that, at present, it is thought to be related to perverse reactions, neurological factors, endocrine disorders, pathogenic microbial infections, etc., which can be induced by high temperature, humid environments and other factors, resulting in patients with itching in the ear, flaking, secretion oozing, blisters and other symptoms, so it is easy to itch behind the ear when scratched and running water situation.
2. Contact dermatitis: this disease is mainly caused by the skin behind the ear in contact with exogenous substances, commonly found in eyeglass frames, animal dander, pollen, cleaning and toiletries, etc., localized blisters, itching, swelling, etc., if the itch is inadvertently scratched the blisters, the itchy behind the ear on the scratching of the performance of running water.
It is suggested that there may be other reasons for the itching behind the ears, it is recommended that the patient go to the hospital, improve the relevant examination, to clarify the specific causes of targeted treatment.