If the genitals itch, then the possible causes are: first, local or systemic allergies, such as allergies caused by contact with allergens or oral medications. In addition to itchy genitalia, it may be accompanied by a red rash or a wind-blown change on the genitalia. In cases of severe itching, the patient can scratch with his hands and develop blood marks or localized bleeding. Usually there is a history of allergen exposure, stop contact with the relevant allergens, and accompanied by anti-allergy drugs, the symptoms can soon be relieved. Second, when there is a fungal infection can appear local itching, external genitalia because hidden in the perineum area, local poor ventilation or often appear damp, or local cleaning is not enough to easily colonize bacteria or fungi, such as yeast-like fungi. The symptoms of itching can occur due to increased bacterial virulence and inadequate local cleanliness, resulting in increased bacterial multiplication. This may be accompanied by an increased milky or cheese-like discharge, or a local rash or peeling skin. A pathogenic test should be performed to confirm the diagnosis and treatment with cleansing or topical medication.