After waking up in the morning, the hand may feel a little swollen because of the following reasons: 1, it is possible that the hand is accidentally pressed by the body or the person sleeping next to it for a long time when sleeping, which leads to local ischemia and swelling. 2, it may be an allergic reaction of the hand. For example, before going to bed at night or eating allergy-prone food for dinner or in patients with chronic urticaria, the presence of allergic conditions may also lead to local swelling of the hands. But usually there is a combination of itchy skin or generalized urticaria.