Nipple pain during breastfeeding for 40 days should find the cause of the pain, which may be caused by feeding style, mastitis, breast hyperplasia, etc. Adjustment of feeding style, physiotherapy, medication or even surgery should be carried out to deal with the cause of the pain. 1. Feeding style: If the mother’s feeding style is not right, or the baby sucks inappropriately, which causes the nipple skin to break down and cause infection, and does not stop breastfeeding in time, and often stimulates, which results in the break down area not healing, causing pain, the mother should wait for the wound to heal before breastfeeding to adjust the feeding style, and clean up in time after feeding, to keep the nipple clean and fresh. 2. Mastitis: generally occurs in new mothers, due to milk stagnation leading to the formation of mastitis or breast abscess, causing nipple tenderness, should go to the hospital in time, under the guidance of the doctor to use antibiotics, such as (penicillin or cephalosporin), and if there is a large abscess formation should be surgically drained. 3. Mammary gland hyperplasia: breastfeeding mammary gland hyperplasia patients may also have nipple tenderness, we should carry out breast massage, to promote milk excretion, or through hot compresses to relieve nipple pain. There may also be other causes of nipple pain during lactation for 40 days. The above medications should be used under the guidance of a doctor.