Neurodermatitis is a common chronic inflammatory skin disease characterized by episodic severe itching and lichenoid skin changes. Its causes may be related to various factors including neuropsychiatric factors, diet, local skin irritation, gastrointestinal dysfunction, and endocrine disorders. It commonly occurs in the neck, elbows, knees, sacrococcygeal region, perineum, and around the anus. The lesions are characterized by pinhead- or rice-grain-sized polygonal flat papules, which are pale red, pale brown, or normal skin colored, with a hard and glossy texture. They may be covered with a small amount of scale, and over time, the lesions can merge into large plaques, with the local skin becoming thickened and rough, showing lichenoid changes. Allergic dermatitis is an allergic reaction disease caused by contact with allergens. Its lesions are diverse, which can be erythema, papules, vesicles, swelling, and accompanied by itching. Therefore, localized allergic dermatitis due to improper treatment, lack of timely treatment, or repeated scratching, can develop into neurodermatitis.