The main causes of nipple inflammation include the following: First, it is due to inflammation of the nipple itself, most commonly in patients with nipple invagination, when there is nipple invagination localized easily stored nipple secretions or surrounding bacteria causing an inflammatory reaction, there will be localized redness, swelling, tenderness, and some patients will lead to inflammation within the breast. The local sebaceous secretion of the nipple is so strong that inflammation can easily occur even without nipple invagination. Secondly, it is caused by the inflammatory reaction of the breast itself. When there is mastitis during breastfeeding, if the inflammation is not well controlled, the nipple will also become inflamed along with it. The third is due to the inflammatory disease of the breast ducts caused by the reaction, the nipple is actually dozens of breast ducts together, each of the ducts if the inflammatory disease, the nipple this part will also be infected with the development of the disease.