But if the injury just occurred immediately with the drug wash, the affected area of the blood vessels will intensify the expansion of edema, blood seepage will also be aggravated, not only will enhance the pain, but also very easy to cause the soft tissue adhesions and local function weakening. Therefore, cold compresses should be applied immediately after the injury occurs, which can make the damaged area vasoconstricted and reduce bleeding, swelling and pain. To the third or fourth day of the injury and then use medicinal washing, used for several days, you can receive the effect of pain and swelling.