Red rashes on the neck may be related to conditions such as contact dermatitis, prickly heat, eczema, and ringworm, and need to be removed through life adjustments and medication according to the cause. 1. Contact dermatitis: If the patient is allergic to clothing or necklaces, cosmetics and other items, it will cause itching, red rash and other symptoms. It is recommended to remove the allergens, and take oral loratadine, fexofenadine and other medications, together with topical application of Denadyl cream to relieve. 2. Prickly heat: If the temperature is too high, sweat secretion is impaired, prickly heat can grow in the neck area. You need to keep the area dry and clean, and apply glycerite lotion to relieve the symptoms; if there is itching, you can also take oral loratadine to relieve the symptoms. 3. Eczema: Eczema patients will have red rashes or papules, accompanied by intense itching. Glucocorticoid creams such as compound dexamethasone cream can be applied for relief, and oral cetirizine and other medications can be taken for treatment. 4. Ringworm: Patients with fungal infections will have a red rash with intense itching. Miconazole, ketoconazole and other drugs can be applied to treat the disease, and in severe cases, oral itraconazole, terbinafine and other drugs are also needed to treat the disease. Due to the more complex causes, it is recommended that patients go to the regular hospital for a clear diagnosis, and the drugs need to be used in strict compliance with the doctor’s instructions.