Wearing a necklace with neck allergy may be a sign of contact dermatitis where the skin comes in contact with certain materials of the necklace and develops an allergy. In this case, avoid further contact with necklaces of similar materials. Treatment can be through external and oral medication. 1, topical drugs: when there is no obvious oozing of the skin lesions, hydrocortisone butyrate cream can be applied for anti-inflammatory and anti-allergic. When there is localized erosion and exudation, it is necessary to use 3% boric acid solution for wet compresses, and then apply glucocorticoid ointment after drying. 2, oral drugs: oral loratadine or cetirizine and other antihistamines to relieve allergic symptoms; serious conditions require oral glucocorticoids. The above medication should be used under the guidance of a doctor, avoid self-medication, wearing a necklace may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, give targeted treatment or treatment.