Ice is used after an injury to reduce swelling and decrease pain.
Ice decreases blood flow to the injured tissue and reduces inflammation. Ice should be used for the first 2 to 3 days after an injury or until the swelling goes away. For instance, if you sprained your ankle 5 days ago and it is still swollen, you should continue to use ice. You can make ice packs by placing ice cubes or crushed ice in a Ziploc-type plastic bag or you can use a commercial frozen gel pack. To avoid frostbite, do not put an ice pack directly on your skin.