If the local skin becomes black and purple, this is a bad performance. It means that a local abscess has been formed and tissue necrosis has occurred, and it is necessary to go to a regular hospital for a detailed examination as soon as possible, and if necessary, it is necessary to perform a surgical incision to drain the pus, to avoid the abscess from breaking out on its own. Although the abscess is considered to be a way to cure the disease, but it is easy to lead to the local trauma has become very large, so even after the recovery, it will form a more obvious scar. Surgical incision and drainage of pus, the surgical incision is more neat, the scope of the relative trauma is very small, the scar will not be too obvious. If a localized abscess has formed, it is recommended to go to a regular hospital for surgical treatment as early as possible, and never let the disease develop without taking this approach because of the fear of surgery.