Arm pain after underarm surgery may be caused by surgical stimulation, local infection, not fully recovered, etc. It needs to be dealt with according to the cause through dietary regimen, recovery regimen and medication. 1. Surgical stimulation: As the underarm surgery process requires incision, when the anesthetic recedes, the surrounding muscle tissue is stimulated, which will cause radioactive pain. At this time, you need to rest more, pay attention to strengthen nutrition, you can do some light exercise to promote local blood circulation. 2. Local infection: If the wound is contaminated after the surgery, secondary infection will occur, and the wound will become red, swollen, painful and pus-filled, which will spread to the surrounding area in serious cases. It is necessary to carry out timely debridement treatment, regular dressing changes, with the use of amoxicillin, cefuroxime and other antibiotics to control the infection. 3. Not fully recovered: after the operation, the wound area needs some time to recover, due to the lack of recovery time, the arm area will also have pain. Need to strengthen the change of medicine, good rehabilitation exercise, more rest, with the passage of time, the surgical site pain will also be relieved. It is recommended that patients pay more attention to observation, timely medical examination when necessary, actively cooperate with the doctor’s treatment, not self-medication.