Swelling of the arm and hand is commonly caused by the following reasons: first, local injury or too much activity caused by local injury or too much activity will lead to muscle swelling, while lactic acid buildup, need to increase rest in a timely manner. At the same time, hot water or hot water bags can be used for hot compresses, and can be appropriate to do physical therapy to promote the recovery of swelling. You should also pay attention to your diet and consume more vitamin and fiber-rich foods, such as fruits and green vegetables. Drinking more warm water and consuming more food rich in high quality protein, such as fish and shrimp, can help to relieve the swelling. Second, venous thrombosis, generally the upper limbs will appear swelling, and at the same time can be combined with pain, need to go to the hospital in a timely manner to perform routine blood, coagulation four and ultrasound of the upper limbs to clarify. If it is the disease, blood circulation and blood stasis removal should be given in time, and if necessary, thrombolytic therapy is also needed. In short, if the swelling persists, it is necessary to go to the hospital promptly to clarify the cause.