Purplish and blackened flesh of the nail groin infection usually requires incision and drainage, please follow the doctor’s instructions. The purple and black flesh of onychomycosis is often indicative of localized infection or hematoma under the nail, which should be treated with local antiseptic coating, followed by incision and drainage. Usually, a longitudinal incision will be made along the nail sulcus to drain the pus; for abscesses at the root of the nail, it may be necessary to remove part of or even the whole fingernail (toenail). Regular postoperative dressing changes and drainage of pus may be required. Oral antibiotics, such as amoxicillin and cefaclor, should also be considered to prevent infection. It is recommended that the patient consult the doctor in time, and follow the doctor’s instructions to actively treat. At the same time, pay attention to finger (toe) nail hygiene, keep hands dry, clean.