Hand cramps are usually caused by muscle spasms and muscle contraction, which may be due to arteriosclerosis, cold weather, strenuous exercise can lead to local blood circulation disorders, muscle contraction and spasm. It may also be caused by calcium deficiency, which is accompanied by difficulty in falling asleep, easy to wake up, excessive sweating, decreased resistance, you can check the blood calcium, or take a film, calcium deficiency can take Calcium Erqi, Calcium Gluconate, and children can take Icosin and other timely supplemental calcium supplements.