Patients with swollen arms with injections can often be treated in different ways depending on the degree of local swelling. First, if the degree of swelling at the patient’s arm is heavy, it is necessary to clarify whether there is local hematoma formation under the skin through local ultrasound examination. Patients with hematoma formation need to apply local ice to promote capillary constriction and avoid progressive increase of hematoma. If the patient has a large volume of hematoma, local anesthesia can be used to remove the subcutaneous hematoma and strengthen the trauma to completely stop bleeding. Postoperative treatment such as anti-infection, analgesia and edema reduction can solve the symptoms of arm swelling faster. Secondly, if the patient is swollen due to soft tissue injury at the injection site, the degree of swelling is often lighter at this time, and the local swelling symptoms can be reduced by local external rubbing of blood circulation and stasis cream, futalin ointment, and oral administration of swelling and painful an and other drugs to promote faster recovery of local soft tissue injury.