When you see a little swelling, it is a very common misconception that you should apply heat. The swelling shows the onset of your pain and inflammation. If you apply heat, it will dilate the vessels. Through these vessels, more causative agents, which cause inflammation and pain, will rush to your place of injury. That is why heat is not recommended for this stage. When you see some swelling, you should apply ice. Applying ice constricts the blood vessels. Hence, no inflammatory agents reach the hand. After 2-3 days, you should start applying moist heat. Why? Heat dilates the blood vessels and increases the amount of blood in the area. By doing this, the body is now sending nutrients and protective agents to the area, thereby accelerating the healing process. If swelling persists longer than 3 days, seek the advice of a physician or healthcare provider.
Extra tip: Never apply ice without first wrapping it in a towel; putting it directly on the skin can be damaging.Also, moist heat is better than dry heat because it penetrates the skin faster.