Autoimmune bullous eruption localized to a breast reconstruction site: response to niacinamide

A case of bullous pemphigoid responding to niacinamide as monotherapy is reported. Clinically, the patient presented with bullous lesions localized to the left breast. She had a history of a left breast mastectomy for breast cancer. This was followed by radiation therapy to the left chest wall and delayed left breast reconstruction achieved with a transposition flap of the latissimus dorsi muscle. There have been reports of bullous pemphigoid treated with a combination of tetracycline and niacinamide. This is the first report, to our knowledge, of a case of bullous pemphigoid responding to niacinamide alone.