Sleeping up hand swelling may be caused by the following reasons: 1, sleep when other parts of the body pressure on the hand, resulting in long time ischemia of the hand caused by localized swelling, you can carry out hand activities to promote local blood circulation, hand swelling will soon disappear. 2, the hand soft tissue allergic symptoms, it is common that the hand contact with easily allergic to things, such as mites or mosquito bites appeared in the hands of allergic reactions, in addition to hand swelling, there will be itching symptoms. In addition to swelling of the hands, there will be itching symptoms. If the allergy is more severe, it may also affect other parts of the body with an itchy rash.