The redness, swelling and pain around the wound after the scab comes off may be caused by local infection or allergic reaction, incomplete healing of local tissues and other reasons. 1. Local infection: if the disinfection is not thorough when dealing with the wound, resulting in more local bacterial residue, there may be the possibility of infection under the scab after the wound scabs, which will cause redness, swelling and pain around the wound after the scabs fall off. 2. Allergic reaction: the site of wound scab is sensitive, if the site of wound scab is often in contact with some easily allergic substances, there may be allergies, thus causing the surrounding skin redness, swelling and pain and other reactions. 3. Incomplete healing of local tissues: if the wound is deeper, resulting in damage to the dermis layer of the skin, the wound needs a longer period of time to recover, and when the wound scabs come off, some patients will experience redness and swelling of the surrounding skin. It is recommended to go to the hospital as soon as possible for examination and timely treatment according to the doctor’s recommendations.