A red lesion accompanied by itching on the neck requires careful observation of the appearance of the red change. If the lesion is flat and raised, it may be urticaria, which is mainly caused by allergic factors, including diet and exposure to certain gases, and can be treated with oral cetirizine hydrochloride tablets or loratadine tablets. If the red lesions are papular and mildly keratotic to the touch, it may be allergic dermatitis, which can be treated with topical hydrocortisone butyrate cream or Denide cream. If the red areas can be seen with obvious exudation-like changes, it is considered to be eczema, and it is recommended to choose furnace glycolate lotion or zinc oxide cream.