For most injuries, ice is recommended during the first 24 to 48 hours. This helps reduce the pain and swelling that are part of the inflammatory stage of healing.
You can switch to heat when the ankle swelling goes away. The area should not be red or hot to the touch. By this time, the progress with ice has come to a halt. No further improvement in symptoms occurs after using ice.
Heat can be applied for 15 to 20 minutes, depending on the type of heat used. Extreme caution is advised when using a heating pad at home. Never fall asleep with the heating pad on. This can cause skin burns, increased tissue swelling, and delayed healing.