Bruises are caused by bleeding into the tissues underneath or into the skin and can appear immediately or even days after an injury. Bruises can be a sign of deep injury in certain cases, and it is important to note that individuals taking blood thinners bleed and bruise rather easily. To treat bruises, it is important to follow RICE:
Rest the injured area if possible
Ice the injured area for at least 10 minutes by administering ice wrapped in a towel or a cold compress
Compress the injured area if it is swelling by wrapping it in an elastic bandage
Elevate the injured area if possible.
Seek medical care if painful swelling continues, pain persists 3 days after a minor injury, you have frequent large or painful bruises (especially on your face, trunk, or back), you experience bleeding from other locations such as your nose or gums, you bruise easily or have a history of significant bleeding, a lump (hematoma) forms over the bruise, you acutely begin bruising without a prior history of bruising, or if you have a family history of easy bleeding or bruising. These symptoms could be indicators of a more serious health problem, such as a blood disease.
Image obtained from https://commons.wikimedia.org/wiki/File:Upper_Arm_Bruise.jpg
License: CC BY-SA 3.0
Austin, M., Crawford, R., & Armstrong, V. J. (2014). First aid manual. (G. M. Piazza, Ed.) (5th ed.). DK Publishing. https://kuiyem.ku.edu.tr/wp-content/uploads/2016/12/American-College-of-Emergency-Physicians-ACEP-First-Aid-Manual.pdf.
Mayo Clinic Staff. (2020, November 12). Bruise: First aid. Mayo Clinic. https://www.mayoclinic.org/first-aid/first-aid-bruise/basics/art-20056663.